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Vital articles is a list of subjects for which Wikipedia should have corresponding high-quality articles. It serves as a centralized watchlist to track the status of Wikipedia's most essential articles. This is one of the sub-lists of the fifty thousand article Vital articles/Level 5 and is currently under construction.

Articles in the Vital list have their assessments labelled as:

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The progress bar is auto-updated via category count, and the symbols and article counts are updated daily by User:cewbot. Please read the FAQ before modifying the article list.

Total articles: 3,183/3,200 Total 3,183 articles.

Class #Articles
B 626
FGAN 84
C 1,424
Start 949
Stub 74
FFA 54
DGA 72
GA 78
FA 21
LIST 10
A 1
FFAC 1
NA 1

General (85 articles)

  1. Technology (Level 1)
  2. Invention
  3. Innovation
  4. Applied science
  5. Research and development
  6. Technology and society
  7. Technological determinism
  8. Technology life cycle
  9. Technology adoption life cycle
  10. Problem solving
  11. Miniaturization
  12. Scientific instrument
  13. Technology assessment
  14. Technology transfer
  15. Appropriate technology

Creativity, Vocational education, Intellectual property and Patent are listed in the Society and Social Sciences section; Industrial design in the Arts section.
For history of technology, see History#History of science and technology section.

Engineering (70 articles)

Basics (18 articles)

  1. Engineering (Level 2)
  2. Nanotechnology (Level 4)
  3. Nuclear technology (Level 4)
  4. Technical drawing (Level 4)
  5. Engineering ethics
  6. Risk analysis (engineering)
  7. Engineering management
  8. Engineering design process
    1. Requirements analysis
    2. Problem statement
    3. Feasibility study
    4. Engineering optimization
  9. Computer-aided design
  10. Engineering economics
  11. Engineering statistics
  12. Engineering research
  13. Reverse engineering
  14. Engineering studies

Disciplines (52 articles)

  1. Agricultural engineering
  2. Applied mechanics
  3. Biological engineering
    1. Biochemical engineering
    2. Biomedical engineering (Level 4)
    3. Pharmaceutical engineering
  4. Ceramic engineering
  5. Chemical engineering (Level 4)
    1. Chemical reaction engineering
    2. Nuclear engineering
    3. Molecular engineering
    4. Petroleum engineering
    5. Process engineering
    6. Polymer engineering
    7. Plastics engineering
  6. Civil engineering (Level 3)
    1. Architectural engineering (Level 4)
    2. Construction engineering
    3. Earthquake engineering
    4. Environmental engineering
    5. Geotechnical engineering
      1. Directional drilling
    6. Hydraulic engineering
    7. Mining engineering
    8. Structural engineering
    9. Transportation engineering
    10. Highway engineering
  7. Electrical engineering (Level 4)
    1. Computer engineering
  8. Energy engineering
    1. Power engineering
    2. Telecommunications engineering
    3. Electronic engineering
    4. Control engineering
    5. Microwave engineering
    6. Radio-frequency engineering
  9. Engineering physics
  10. Industrial engineering (Level 4)
    1. Computer-aided engineering
    2. Manufacturing engineering
  11. Mechanical engineering (Level 3)
    1. Aerospace engineering (Level 4)
    2. Mechatronics
    3. Railway engineering
    4. Marine engineering
    5. Automotive engineering (Level 4)
  12. Military engineering (Level 4)
  13. Sanitary engineering
  14. Security engineering
  15. Software engineering (Level 4)
  16. Structural analysis
  17. Systems engineering

Agriculture (235 articles)

See Agriculture in the Society category; also see History of Agriculture and related articles under History, or the Everyday life category for basic agricultural products

Basics (11 articles)

  1. Arable land
  2. Crop
    1. Cash crop
    2. Nonfood crop
    3. Fiber crop
  3. Agricultural machinery
  4. Agricultural cycle
    1. Growing season
    2. Season extension
  5. Agricultural land
  6. Pasture

Academic Disciplines (11 articles)

  1. Agricultural science (Level 4)
  2. Agricultural chemistry
  3. Agricultural economics
  4. Agricultural philosophy
  5. Agricultural soil science
  6. Agroecology
  7. Agricultural policy
  8. Agricultural geography
  9. Agricultural education
    1. Agricultural extension
  10. Agrometeorology

Forms (56 articles)

Agriculture (39 articles)

  1. Beekeeping (Level 4)
  2. Cuniculture
  3. Dairy (Level 4)
    1. Dairy farming
  4. Dryland farming
  5. Desert farming
  6. Heliciculture
  7. Rainfed agriculture
  8. Extensive farming (Level 4)
  9. Gardening (Level 4)
  10. Intensive farming (Level 4)
  11. Mechanised agriculture
  12. Orchard (Level 4)
  13. Organic farming (Level 4)
  14. Genetically modified crops
  15. Sustainable agriculture (Level 4)
  16. Pastoral farming
    1. Permaculture
  17. Subsistence agriculture (Level 4)
  18. Urban agriculture (Level 4)
  19. Pastoralism
  20. Shifting cultivation
  21. Regenerative agriculture
  22. Animal-free agriculture
  23. Intensive animal farming
  24. Free range
  25. Hydroponics
  26. Sericulture
  27. Viticulture
  28. Fungiculture
  29. Olericulture
  30. Slash-and-burn
  31. Vertical farming
  32. Polyculture
    1. Multiple cropping
    2. Intercropping
  33. Sharecropping
  34. Tenant farmer
  35. Forest gardening

Aquaculture (17 articles)

  1. Aquaculture (Level 4)
  2. Mariculture
  3. Algaculture
  4. Aquaculture of giant kelp
  5. Fish farming
    1. Aquaculture of catfish
    2. Aquaculture of salmonids
    3. Aquaculture of tilapia
  6. Freshwater prawn farming
  7. Geoduck aquaculture
  8. Integrated multi-trophic aquaculture
  9. Marine shrimp farming
  10. Offshore aquaculture
  11. Organic aquaculture
  12. Raceway (aquaculture)
  13. Scallop aquaculture
  14. Seaweed farming

Pest and disease control (25 articles)

  1. Aerial application
  2. Acaricide
  3. Agrochemical
  4. Agent Orange
  5. Aldrin
  6. Biological pest control
  7. Chemosterilant
  8. DDT
  9. Defoliant
  10. Fumigation
  11. Fungicide
  12. Herbicide
  13. Insecticide
  14. Integrated pest management
  15. Lindane
  16. Malathion
  17. Methoxychlor
  18. Pest (organism)
  19. Pesticide (Level 4)
  20. Rodenticide
  21. Scarecrow
  22. Smother crop
  23. Soil steam sterilization
  24. Tetraethyl pyrophosphate
  25. Toxaphene

Buildings and infrastructure (26 articles)

  1. Apiary
  2. Barn (Level 4)
  3. Farm (Level 4)
  4. Garden (Level 3)
    1. Arboretum
    2. Botanical garden
    3. English landscape garden
    4. Japanese garden
    5. Persian gardens
    6. Spanish garden
  5. Fishery
  6. Fish hatchery
  7. Granary (Level 4)
  8. Grain elevator
  9. Greenhouse
  10. Orangery
  11. Paddy field
  12. Plant nursery
  13. Raised field
    1. Chinampa
    2. Waru Waru
  14. Seedbed
  15. Silo (Level 4)
  16. Stable (Level 4)
  17. Terrace (earthworks)
  18. Ranch

Animal husbandry (21 articles)

  1. Animal husbandry (Level 3)
  2. Animal slaughter
  3. Breed (Level 4)
  4. Culling
  5. Domestication (Level 3)
  6. Goat farming
  7. Animal feed
    1. Fodder
      1. Hay (Level 4)
      2. Straw
    2. Forage
    3. Fish meal
  8. Livestock (Level 4)
  9. Pig farming
  10. Poultry farming
  11. Selective breeding (Level 4)
    1. Animal breeding
    2. Purebred
  12. Sheep farming
  13. Slaughterhouse
  14. Antibiotic use in livestock

Agronomy (29 articles)

Basics (4 articles)

  1. Agronomy (Level 4)
  2. Plant breeding (Level 4)
    1. Cultivar (Level 4)
  3. Crop yield

Agronomical techniques (15 articles)

  1. Nutrient management
  2. Fertilizer (Level 3)
    1. Compost
    2. Vermicompost
    3. Green manure
    4. Guano
    5. Manure
  3. Harvest (Level 4)
    1. Threshing
    2. Winnowing
  4. Irrigation (Level 4)
  5. Tillage (Level 4)
  6. Silage
  7. Sowing
  8. Postharvest

Soil and Soil management (10 articles)

See "Pedology" in Earth Science

  1. Beneficial organism
  2. Cover crop
  3. Crop rotation
  4. Mulch
    1. Plastic mulch
  5. Nitrogen fixation
  6. Norfolk four-course system
  7. No-till farming
  8. Three-field system
  9. Soil salinity control

Horticulture (22 articles)

  1. Horticulture (Level 4)
  2. Espalier
  3. Floriculture
  4. Grafting
  5. Layering
  6. Plant propagation
  7. Pollarding
  8. Pollination management
  9. Pruning
  10. Smudge pot
  11. Topiary
  12. Transplanting
  13. Basal shoot
  14. Pomology
  15. Companion planting
  16. Genetically modified tree
  17. Indigenous horticulture
  18. Urban horticulture
  19. Hardiness (plants)
    1. Hardiness zone
  20. Drought tolerance
  21. Tropical horticulture

Hunting and fishing (18 articles)

  1. Fishing line
    1. Dropline
    2. Longline fishing
    3. Trotline
  2. Fishing net
    1. Gillnetting
    2. Seine fishing
  3. Fishing rod
    1. Fish hook
    2. Fishing lure
    3. Fishing reel
    4. Fishing float
  4. Fish trap
    1. Crab trap
    2. Fishing weir
    3. Lobster trap
  5. Trapping
    1. Bait (luring substance)

Trees and Forestry (5 articles)

  1. Agroforestry
  2. Arboriculture
  3. Silviculture
  4. Coppicing
  5. Controlled burn

Agriculture, Labor and Economy (8 articles)

  1. Community-supported agriculture
    1. Teikei
  2. Corporate farming
  3. Family farm
  4. Agricultural cooperative
  5. Working animal
  6. Agribusiness
  7. Agricultural marketing

Agriculture and Ecology (3 articles)

  1. Environmental impact of agriculture
  2. Agricultural expansion
  3. Agricultural pollution

Agricultural machinery and tools

See "Agricultural tools" and "Farm and Garden Machinery" in Technology : Machinery and tools

Biotechnology (43 articles)

See also : Selective Breeding in Agriculture; Fermentation in Biology

  1. Biotechnology (Level 3)
  2. Genetic engineering (Level 3)
  3. Recombinant DNA
    1. Genetically modified organism (Level 4)
    2. CRISPR
    3. Molecular cloning
  4. Cloning (Level 4)
    1. Somatic cell nuclear transfer
  5. Gel electrophoresis (Level 4)
  6. Polymerase chain reaction (Level 4)
  7. Western blot
  8. Cyborg
  9. Whole genome sequencing
  10. Tissue engineering
  11. Biochip
  12. De-extinction
  13. Genome editing
  14. Nuclear transfer
  15. Pharming (genetics)
  16. Biomimetics
  17. DNA microarray
  18. Micropropagation
  19. Biological hazard
  20. Bioterrorism
    1. Agro-terrorism
  21. Pharmacogenomics
  22. Biopharmaceutical
  23. Genetic testing
  24. Synthetic biopolymer
  25. Biomaterial
  26. Agricultural biotechnology
  27. Environmental biotechnology
  28. Bioreactor
  29. Gene therapy
  30. Stem-cell therapy
  31. Antisense therapy
  32. Organ printing
  33. Protein engineering
  34. Activated sludge
  35. Anaerobic digestion
  36. Bioleaching
  37. Biomining
  38. Somatic fusion

Communication, media, and computing technology (750 articles)

For abstract topics in computer science, see Mathematics: Theoretical computer science (Level 5)

Computing and information technology basics (11 articles)

  1. Computing (Level 4)
  2. Information technology (Level 4)
  3. Abacus (Level 4)
  4. Calculator (Level 4)
  5. Counting board
  6. Data (computer science) (Level 4)
    1. Data communication (Level 4)
    2. Metadata
  7. File sharing
  8. Human–computer interaction
  9. Open source

Computer science (16 articles)

  1. Computer science (Level 3)
  2. Artificial intelligence (Level 3)
  3. Computer architecture (Level 4)
  4. Computer simulation (Level 4)
  5. Parallel computing (Level 4)
    1. General-purpose computing on graphics processing units
  6. Augmented reality
  7. Mixed reality
  8. Virtual reality
  9. Concurrent computing
    1. Monitor (synchronization)
  10. Floating-point arithmetic
  11. Real-time computing
  12. Computer graphics (computer science)
    1. Color management
    2. Transform, clipping, and lighting

Computer architecture concepts (27 articles)

  1. Cache (computing)
  2. Cache coherence
  3. Distributed computing
    1. Computer cluster
    2. Grid computing
  4. Cloud computing
  5. Optical computing
  6. DNA computing
  7. Quantum computing
  8. Von Neumann architecture
  9. 8-bit computing
  10. 16-bit computing
  11. 32-bit computing
  12. 64-bit computing
  13. Endianness
  14. Multithreading (computer architecture)
  15. Multiprocessing
  16. Instruction set architecture
    1. x86
      1. x86-64
    2. ARM architecture family
    3. IBM POWER architecture
    4. MIPS architecture
    5. Very long instruction word
  17. System time
    1. Epoch (computing)
    2. Unix time

Computer security (39 articles)

  1. Computer security (Level 4)
  2. Firewall (computing)
  3. Transport Layer Security
  4. Security bug
    1. Zero-day (computing)
  5. Denial-of-service attack
    1. Botnet
  6. Copy protection
    1. Digital rights management
  7. Malware (Level 4)
    1. Computer virus
    2. Computer worm
    3. Trojan horse (computing)
    4. Ransomware
    5. Spyware
      1. Keystroke logging
  8. Cryptography (Level 3)
    1. Block cipher
    2. Brute-force attack
    3. Caesar cipher
    4. Cipher
    5. Cryptanalysis
    6. Digital signature
    7. Encryption (Level 4)
    8. Enigma machine
    9. Key (cryptography)
    10. One-time pad
    11. Public-key cryptography
      1. Diffie–Hellman key exchange
      2. RSA (cryptosystem)
    12. Symmetric-key algorithm
  9. Authentication (Level 4)
    1. Password
    2. Security token
    3. Multi-factor authentication
  10. Security through obscurity
    1. Obfuscation (software)
    2. Steganography
  11. Zombie (computing)

Computer hardware (80 articles)

  1. Computer hardware (Level 4)
  2. Computer (Level 2)
    1. Personal computer
    2. Home computer
    3. Desktop computer
    4. Laptop
      1. 2-in-1 laptop
    5. Mobile device
      1. Tablet computer
      2. Wearable computer
    6. Gaming computer
    7. IBM PC compatible
    8. Mainframe computer
    9. Supercomputer (Level 4)
    10. Workstation
  3. Booting (Level 4)
    1. BIOS
      1. UEFI
    2. Multi-booting
    3. Reboot
  4. Processor (computing)
    1. Central processing unit (Level 4)
      1. Microprocessor
        1. Multi-core processor
    2. Coprocessor
  5. Motherboard
  6. Processor register
  7. Floating-point unit
  8. Graphics processing unit
  9. Arithmetic logic unit
  10. Digital signal processor
  11. Bus (computing)
    1. SATA
    2. Parallel ATA
    3. Industry Standard Architecture
    4. Peripheral Component Interconnect
    5. PCI Express
    6. Front-side bus
  12. Expansion card
    1. Sound card
    2. Graphics card
    3. PC Card
    4. ExpressCard
  13. Modem
  14. Device driver
  15. Intel High Definition Audio
  16. Moore's law
  17. Clock rate
  18. Embedded system
  19. Real-time clock
  20. Computer case
  21. Computer cooling
  22. Analog computer
  23. Stored-program computer
  24. Hardware acceleration
  25. Plug and play

User interface (24 articles)

  1. User interface (Level 4)
  2. Graphical user interface
    1. Window (computing)
    2. X Window System
  3. Command-line interface
  4. Cut, copy, and paste
  5. Peripheral
    1. Computer keyboard
    2. Computer monitor (Level 4)
    3. Pointing device
      1. Computer mouse (Level 4)
      2. Touchpad
      3. Touchscreen (Level 4)
  6. Computer port (hardware)
    1. IEEE 1394
    2. USB
      1. USB-C
    3. D-subminiature
    4. Digital Visual Interface
    5. DisplayPort
    6. HDMI
    7. VGA connector
    8. Thunderbolt (interface)
  7. Webcam

Computer software (37 articles)

  1. Software (Level 4)
  2. Application software
  3. Database (Level 4)
    1. Data mining
    2. Big data
  4. Mobile app
  5. Open-source software (Level 4)
  6. Spreadsheet (Level 4)
  7. System software
  8. Web application
    1. Webmail
    2. Web content management system
  9. Web browser (Level 4)
  10. Word processor (Level 4)
  11. Desktop publishing
  12. Plug-in (computing)
  13. POSIX
  14. GNU Project
  15. Input method

Operating systems (16 articles)

  1. Firmware
  2. Operating system (Level 4)
    1. Real-time operating system
  3. Virtual machine
  4. Kernel (operating system)
  5. Job (computing)
  6. Task (computing)
  7. Thrashing (computer science)
  8. Thread (computing)
  9. Preemption (computing)
  10. Process (computing)
  11. Computer multitasking
  12. Scheduling (computing)
  13. System call
  14. Time-sharing
  15. Working set

Utility software (2 articles)

  1. Antivirus software
  2. Backup software

Data storage and memory (76 articles)

For units of information (bit, byte, megabyte, etc.), see Physical sciences/Basics and measurement

  1. Computer file (Level 4)
  2. Backup
  3. Barcode (Level 4)
  4. File system (Level 4)
    1. HFS Plus
    2. File Allocation Table
    3. NTFS
    4. ext4
    5. ISO 9660
    6. Universal Disk Format
  5. Directory (computing)
  6. Filename extension
  7. Data storage (Level 4)
    1. Computer data storage
    2. Cloud storage
  8. RAID
  9. Disk partitioning
  10. Computer memory
  11. Binary file
  12. Text file
    1. Formatted text
    2. Plain text

File format (26 articles)

  1. File format
  2. Archive file
    1. ZIP (file format)
    2. RAR (file format)
    3. 7z
  3. Document file format
    1. Office Open XML
    2. OpenDocument
    3. PDF
  4. Image file format
    1. GIF
    2. JPEG
    3. TIFF
    4. PNG
    5. SVG
  5. Audio coding format
    1. WAV
    2. MP3
    3. Advanced Audio Coding
  6. Video coding format
    1. Advanced Video Coding
    2. DivX
  7. Container format
    1. MPEG-4
    2. WebM
    3. Ogg

Volatile memory (5 articles)

  1. Volatile memory
  2. Random-access memory (Level 4)
    1. Dynamic random-access memory
    2. Static random-access memory
  3. Virtual memory

Non-volatile memory (23 articles)

  1. Non-volatile memory
  2. Read-only memory (Level 4)
  3. Magnetic storage
    1. Floppy disk
    2. Hard disk drive (Level 4)
    3. Magnetic tape (Level 4)
      1. Magnetic-tape data storage
      2. VHS
      3. Betamax
  4. Flash memory
    1. USB flash drive
    2. Solid-state drive
    3. Memory card (Level 4)
      1. CompactFlash
      2. SD card
      3. MultiMediaCard
      4. Universal Flash Storage
  5. Optical disc (Level 4)
    1. Compact disc
    2. DVD
    3. LaserDisc
    4. HD DVD
    5. Blu-ray

Networks (68 articles)

  1. Computer network (Level 4)
    1. Intranet
  2. Email (Level 4)
    1. Spamming
    2. Simple Mail Transfer Protocol
    3. Internet Message Access Protocol
  3. Ethernet (Level 4)
  4. Router (computing) (Level 4)
  5. Routing
  6. Wi-Fi (Level 4)
  7. Bluetooth
  8. Cellular network
    1. GSM
  9. Server (computing)
  10. Client–server model
  11. Network topology
  12. Network switch
  13. Network packet
  14. Network interface controller
  15. Node (networking)
  16. Internet of things
  17. Wireless mesh network
  18. Content delivery network
  19. Private network
  20. Subnet
  21. Tunneling protocol
  22. Proxy server
  23. Reverse proxy

Internet (40 articles)

For Internet culture, see Society and social sciences/Culture#Internet medium

  1. Internet (Level 3)
  2. ARPANET
  3. CSS
  4. Communication protocol
  5. Common Gateway Interface
  6. File Transfer Protocol
  7. Hashtag
  8. HTML (Level 4)
    1. HTML5
  9. HTTP (Level 4)
    1. HTTPS
  10. Online chat
    1. Internet Relay Chat
  11. Internet protocol suite (Level 4)
    1. Internet Protocol
    2. IP address
    3. Internet Protocol version 4
    4. IPv6
    5. Transmission Control Protocol
  12. Internet service provider
  13. Peer-to-peer file sharing
    1. BitTorrent
    2. EDonkey network
    3. Napster
  14. Social media (Level 4)
    1. Blog
    2. Bulletin board system
    3. Chat room
    4. Internet forum
    5. Online dating
    6. Social networking service
    7. Usenet
  15. Web 2.0
  16. Search engine (Level 4)
  17. Tor (network)
  18. Website (Level 4)
    1. Wiki
  19. World Wide Web (Level 4)
    1. Dark web
    2. Deep web

Software development (119 articles)

General (64 articles)

  1. Software development
  2. Software prototyping
  3. Reusability
  4. Software portability
  5. Transparency (human–computer interaction)
  6. Library (computing)
  7. Formal specification
  8. Formal verification
  9. Software design
  10. Abstraction (computer science)
  11. Variable (computer science)
  12. Function (computer programming)
  13. Pointer (computer programming)
  14. Recursion (computer science)
  15. Iteration
  16. Computer programming (Level 4)
  17. Flowchart
  18. Source code
  19. Bytecode
  20. Object code
  21. Executable
    1. .exe
  22. Parameter (computer programming)
  23. Collation
  24. Universal Product Code
  25. Character encoding (Level 4)
    1. ASCII
    2. Mojibake
    3. Unicode
      1. UTF-8
  26. Error correction code
  27. Compiler (Level 4)
  28. Interpreter (computing)
  29. Control flow
  30. Macro (computer science)
  31. Regular expression
  32. Calling convention
  33. Programming language (Level 4)
  34. Programming paradigm (Level 4)
    1. Functional programming (Level 4)
    2. Structured programming (Level 4)
    3. Modular programming
    4. Object-oriented programming (Level 4)
    5. Declarative programming
    6. Imperative programming
    7. Logic programming
  35. API
    1. Carbon (API)
    2. Cocoa (API)
    3. Open Database Connectivity
    4. Windows API
      1. DirectX
        1. Direct3D
    5. OpenGL
    6. Vulkan
    7. Glide (API)
  36. Software testing
  37. Software bug
  38. Debugging
  39. Application checkpointing
  40. Exception handling
  41. Version control
  42. Software maintenance
  43. Software documentation

Programming languages (41 articles)

  1. Syntax (programming languages)
  2. Metasyntax
  3. Backus–Naur form
  4. Type conversion
  5. Data type
  6. Delimiter
  7. Operator overloading
  8. Language binding
  9. Low-level programming language
    1. Machine code
    2. Assembly language (Level 4)
  10. High-level programming language
    1. C (programming language) (Level 4)
    2. C++
    3. C Sharp (programming language)
    4. Objective-C
    5. Delphi (software)
    6. Haskell
    7. Java (programming language) (Level 4)
    8. Kotlin (programming language)
    9. Lisp (programming language)
    10. Lua (programming language)
    11. Scala (programming language)
    12. Swift (programming language)
    13. Visual Basic (.NET)
  11. Shading language
  12. R (programming language)

Data modeling languages (1 article)

  1. SQL

Markup languages (1 article)

  1. XML

Scripting languages (6 articles)

  1. Python (programming language)
  2. Ruby (programming language)
  3. PHP
  4. Perl
  5. JavaScript (Level 4)
  6. Shell script

"Historical" languages (6 articles)

  1. ALGOL
  2. BASIC
  3. Pascal (programming language)
  4. Fortran
  5. Ada (programming language)
  6. COBOL

Artificial intelligence concepts (14 articles)

  1. AI alignment
  2. Artificial general intelligence
  3. Artificial neural network
  4. Computer chess
  5. Computer Go
  6. Existential risk from artificial general intelligence
  7. Machine learning
  8. Natural language processing
    1. Speech recognition
    2. Machine translation
  9. Philosophy of artificial intelligence
  10. Technological singularity
  11. Turing test
  12. Weak artificial intelligence

Other media and communication technology (98 articles)

See also Arts: Literature; Society: Mass media
Physical and analog media are also included here

  1. Broadcasting (Level 3)
  2. Communications satellite (Level 4)
  3. Display device
    1. Cathode-ray tube (Level 4)
    2. Flat-panel display (Level 4)
      1. Liquid-crystal display (Level 4)
      2. microLED
      3. OLED
      4. Plasma display
  4. Ebook
    1. E-reader
  5. Image (Level 4)
  6. Image scanner (Level 4)
  7. Mail (Level 3)
    1. Courier (Level 4)
    2. Postage stamp (Level 4)
    3. Pigeon post
  8. Polygraph (duplicating device)
    1. Autopen
  9. Portable media player
  10. Printing (Level 3)
    1. Book (Level 2)
    2. Photocopier (Level 4)
    3. Printer (computing) (Level 4)
    4. Printing press (Level 4)
      1. Font
      2. Movable type
      3. Print on demand
  11. QR code
  12. Radio (Level 3)
    1. Amateur radio (Level 4)
    2. Antenna tuner
    3. Radio broadcasting (Level 4)
      1. FM broadcasting
      2. AM broadcasting
      3. Shortwave radio
    4. Radio receiver
      1. Crystal radio
      2. Superheterodyne receiver
      3. Transistor radio
    5. Software-defined radio
    6. Transmitter
    7. Walkie-talkie
  13. Sound recording and reproduction (Level 4)
    1. Cassette tape
    2. Loudspeaker (Level 4)
    3. Phonograph
      1. Phonograph record
    4. Headphones
    5. Microphone (Level 4)
  14. Speech synthesis (Level 4)
  15. Telecommunications (Level 3)
    1. Demodulation
    2. Modulation (Level 4)
      1. Amplitude modulation
      2. Frequency-hopping spread spectrum
      3. Frequency modulation
      4. Frequency-shift keying
      5. Phase modulation
    3. Submarine communications cable
    4. Telegraphy (Level 4)
      1. Electrical telegraph
      2. Flag semaphore
    5. Telephony
      1. Code-division multiple access
      2. Telephone (Level 3)
      3. Landline
      4. Mobile phone (Level 3)
      5. Satellite phone
      6. Smartphone (Level 4)
    6. Text messaging (Level 4)
    7. Videotelephony
  16. Television (Level 3)
    1. Analog television
      1. NTSC
      2. PAL
      3. SECAM
    2. Color television
    3. Digital television
      1. ATSC standards
      2. Digital multimedia broadcasting
      3. Digital Terrestrial Multimedia Broadcast
      4. DVB
      5. ISDB
    4. High-definition television
    5. Ultra-high-definition television
    6. Mechanical television
    7. Cable television (Level 4)
    8. Satellite television (Level 4)
    9. Streaming media
    10. Streaming television
    11. Terrestrial television
  17. Typewriter (Level 4)
    1. QWERTY
  18. Video (Level 4)
    1. Video camera (Level 4)
    2. Videocassette recorder
  19. Digital video recorder

Specific hardware (44 articles)

See also video game hardware section under games for early Home Computers

  1. Amazon Kindle
  2. Amiga
  3. Arduino
  4. Asus Eee PC
  5. Chromebook
  6. Commodore 64
  7. Deep Blue (chess computer)
  8. iMac
  9. iPad
  10. iPhone
  11. iPod
  12. Mac (computer)
  13. MSX
  14. Netbook
  15. PC-98
  16. Raspberry Pi
  17. Samsung Galaxy
  18. ThinkPad
  19. Walkman
  20. ZX Spectrum

Early computers (24 articles)

  1. Analytical engine
  2. Antikythera mechanism
  3. Atanasoff–Berry computer
  4. Atlas (computer)
  5. Colossus computer
  6. Difference engine
  7. EDSAC
  8. EDVAC
  9. ENIAC (Level 4)
  10. IBM Personal Computer
  11. ILLIAC
  12. SEAC (computer)
  13. SWAC (computer)
  14. IBM 7030 Stretch
  15. UNIVAC LARC
  16. Manchester computers
    1. Manchester Baby
    2. Manchester Mark 1
  17. Harvard Mark I
  18. TRS-80
  19. UNIVAC I
  20. Whirlwind I
  21. Z3 (computer)
  22. Apple II

Specific software (72 articles)

Artificial Intelligence (3 articles)

  1. AlphaGo
  2. TensorFlow
  3. ChatGPT

Browsers (7 articles)

  1. Firefox
  2. Google Chrome
  3. Internet Explorer
  4. Microsoft Edge
  5. Netscape (web browser)
  6. Opera (web browser)
  7. Safari (web browser)

Communication (1 article)

  1. Microsoft Outlook

Development (3 articles)

  1. Electron (software framework)
  2. "Hello, World!" program
  3. Visual Studio

Multimedia (14 articles)

  1. Adobe Creative Suite
    1. Adobe After Effects
    2. Adobe Flash
    3. Adobe Photoshop
  2. FFmpeg
  3. Final Cut Studio
  4. Foobar2000
  5. GarageBand
  6. GIMP
  7. Inkscape
  8. iTunes
  9. Microsoft Paint
  10. OBS Studio
  11. VLC media player

Office and Data Management (10 articles)

  1. Adobe Acrobat
  2. BitTorrent (software)
  3. Emacs
  4. FileZilla
  5. LibreOffice
  6. Microsoft Office
  7. MySQL
  8. TeX
  9. WinRAR
  10. Vim (text editor)

Operating Systems (26 articles)

  1. Android (operating system) (Level 4)
  2. iOS (Level 4)
  3. DOS
    1. MS-DOS (Level 4)
  4. FreeRTOS
  5. Mac operating systems (Level 4)
    1. Classic Mac OS
    2. macOS
  6. Microsoft Windows (Level 4)
    1. Windows 3.1x
    2. Windows 9x
      1. Windows 95
      2. Windows 98
    3. Windows NT
      1. Windows XP
      2. Windows Vista
      3. Windows 7
      4. Windows 10
  7. Symbian
  8. Unix (Level 4)
  9. Unix-like
    1. Linux (Level 4)
      1. Arch Linux
      2. Debian
      3. Fedora Linux
      4. Ubuntu

Science and Engineering (2 articles)

  1. AutoCAD
  2. MATLAB

System (3 articles)

  1. GDK
  2. KDE
  3. Wine (software)

Virtualization (3 articles)

  1. Java virtual machine
  2. VirtualBox
  3. VMware

Specific websites and other computing services (63 articles)

Cloud server (4 articles)

  1. Akamai Technologies
  2. Amazon Web Services
  3. Cloudflare
  4. Google Cloud Platform

Multimedia (6 articles)

  1. Flickr
  2. Netflix
  3. Pornhub
  4. Spotify
  5. Steam (service)
  6. YouTube (Level 4)

E-commerce (7 articles)

  1. Airbnb
  2. Alipay
  3. Craigslist
  4. eBay
  5. PayPal
  6. Tmall
  7. Uber

Portals/Platform sites (6 articles)

  1. Baidu
  2. Google (Level 4)
  3. MSN
  4. Sohu
  5. Yahoo!
  6. Yandex

Utility (8 articles)

  1. GitHub
  2. Google Maps
  3. Internet Archive
  4. IMDb
  5. Rotten Tomatoes
  6. Urban Dictionary
  7. Wikipedia (Level 4)
  8. Wix.com

Science (1 article)

  1. Berkeley Open Infrastructure for Network Computing

Search engines (3 articles)

  1. Google Search
  2. Microsoft Bing
  3. Yahoo! Search

Social network and blogging (28 articles)

  1. 2channel
  2. 4chan
  3. Blogger (service)
  4. DeviantArt
  5. Discord
  6. Facebook (Level 4)
    1. Instagram
  7. ICQ
  8. KakaoTalk
  9. Line (software)
  10. LinkedIn
  11. Myspace
  12. Pinterest
  13. Reddit
  14. Slack (software)
  15. Skype
  16. Snapchat
  17. Tencent QQ
  18. TikTok
  19. Tinder (app)
  20. Tumblr
  21. Twitch (service)
  22. Twitter
  23. Weibo
  24. Vine (service)
  25. VK (service)
  26. WeChat
  27. WhatsApp

Electronics (117 articles)

For topics in electromagnetism, see Physics:Electromagnetism

General (9 articles)

  1. Electronics (Level 3)
    1. Analogue electronics
    2. Digital electronics
  2. Circuit design (Level 4)
    1. Electronic design automation
    2. Printed circuit board (Level 4)
    3. SPICE
  3. Electronic circuit
    1. Multimeter

Components (36 articles)

  1. Electronic component
  2. Amplifier (Level 4)
    1. Operational amplifier
    2. Vacuum tube (Level 4)
  3. Capacitor (Level 4)
    1. Ceramic capacitor
    2. Electrolytic capacitor
    3. Film capacitor
    4. Leyden jar
    5. Supercapacitor
    6. Variable capacitor
  4. Diode (Level 4)
    1. Light-emitting diode (Level 4)
  5. Electrical connector (Level 4)
  6. Inductor (Level 4)
  7. Power supply (Level 4)
    1. Current source
    2. Voltage source
  8. Resistor (Level 4)
    1. Potentiometer
  9. Switch (Level 4)
    1. Knife switch
    2. Relay (Level 4)
    3. Rotary switch
  10. Transducer
    1. Actuator
      1. Solenoid
    2. Sensor (Level 4)
      1. Avalanche photodiode
      2. Photodiode
      3. Photomultiplier tube
      4. Phototube
      5. Stretch sensor
      6. Thermistor
      7. Thermocouple
  11. Transformer (Level 4)

Consumer electronics (3 articles)

  1. Consumer electronics (Level 4)
  2. AC adapter
  3. Remote control (Level 4)

Digital logic (17 articles)

  1. Asynchronous circuit
    1. Globally asynchronous locally synchronous
  2. Logic gate
    1. AND gate
    2. Digital buffer
    3. Inverter (logic gate)
    4. NAND gate
    5. NOR gate
    6. OR gate
    7. XOR gate
    8. XNOR gate
  3. Adder (electronics)
    1. Binary multiplier
    2. Subtractor
  4. Flip-flop (electronics)
  5. Synchronous circuit
    1. Clock domain crossing

Functional circuits (14 articles)

  1. Bridge circuit
    1. Wheatstone bridge
  2. Electronic oscillator
    1. Clock generator
      1. Clock signal
    2. Crystal oscillator
    3. Variable-frequency oscillator
  3. Frequency mixer
  4. Gyrator
  5. Negative impedance converter
  6. Power inverter
  7. Rectifier
    1. Diode bridge
  8. Voltage regulator

Semiconductors (14 articles)

  1. Semiconductor device (Level 3)
  2. Integrated circuit (Level 3)
    1. Application-specific integrated circuit
    2. Charge-coupled device (Level 4)
    3. Field-programmable gate array
    4. System on a chip
      1. Network on a chip
    5. Very Large Scale Integration
  3. Transistor (Level 4)
    1. Bipolar junction transistor
    2. Field-effect transistor
      1. MOSFET
    3. Transistor–transistor logic
    4. CMOS

Signal processing (17 articles)

  1. Signal processing (Level 4)
    1. Digital signal
  2. Analog-to-digital converter
  3. Digital-to-analog converter
  4. Filter (signal processing) (Level 4)
    1. All-pass filter
      1. Lattice phase equaliser
    2. Band-pass filter
    3. Mechanical filter
    4. High-pass filter
    5. Low-pass filter
  5. Multiplexing
  6. Noise (electronics)
    1. Signal-to-noise ratio (Level 4)
  7. Oscilloscope (Level 4)
  8. Sampling (signal processing)
    1. Nyquist–Shannon sampling theorem

Signal transmission (7 articles)

  1. Antenna (radio) (Level 4)
    1. Antenna array
  2. Electromagnetic shielding
    1. Faraday cage
  3. Transmission line
    1. Coaxial cable
    2. Waveguide (Level 4)

Energy (169 articles)

General (5 articles)

  1. Energy development
  2. Fire (Level 2)
  3. Propellant
  4. Renewable energy (Level 3)
  5. Sustainable energy

Fuel (25 articles)

  1. Fuel (Level 4)
  2. Biofuel (Level 4)
    1. Biomass (energy)
    2. Charcoal (Level 4)
  3. Fossil fuel (Level 3)
    1. Coal (Level 3)
    2. Coke (fuel)
    3. Fracking
    4. Natural gas (Level 3)
      1. Liquefied natural gas
      2. Liquefied petroleum gas
    5. Oil well (Level 4)
      1. Petroleum reservoir
      2. Oil platform
  4. Hydrogen economy
  5. Oil refinery (Level 4)
    1. Aviation fuel
      1. Jet fuel
    2. Diesel fuel
    3. Fuel oil
    4. Gasoline (Level 4)
    5. Kerosene (Level 4)
    6. Liquid fuel
  6. Nuclear fuel
    1. Nuclear fuel cycle

Heating and cooling (10 articles)

  1. Heating, ventilation, and air conditioning (Level 4)
    1. Heat pump
  2. Air conditioning (Level 4)
    1. Evaporative cooler
    2. Passive cooling
    3. Windcatcher
  3. Boiler
  4. Heat exchanger
  5. Refrigeration (Level 3)
    1. Yakhchāl

Lighting (12 articles)

  1. Candle (Level 4)
  2. Electric light (Level 3)
    1. Flashlight
    2. Fluorescent lamp
    3. Incandescent light bulb (Level 4)
    4. Neon lighting
  3. Gas lighting
    1. Gas mantle
  4. Lantern
  5. Oil lamp
  6. Prism lighting
    1. Light tube

Power generation (40 articles)

  1. Power station (Level 4)
    1. Electric generator (Level 4)
      1. Induction generator
    2. Electricity generation (Level 4)
  2. Hydropower (Level 3)
    1. Hydroelectricity (Level 4)
    2. Tidal power
    3. Watermill (Level 4)
  3. Microgeneration
    1. Micro-CHP
  4. Nuclear power (Level 3)
    1. Fusion power
      1. Inertial confinement fusion
      2. Tokamak
    2. Nuclear reactor
      1. Breeder reactor
      2. Molten salt reactor
      3. Heavy water reactor
      4. Small modular reactor
      5. Nuclear marine propulsion
      6. Nuclear meltdown
  5. Solar energy (Level 3)
    1. Solar power (Level 4)
    2. Solar cell (Level 4)
  6. Thermal power station
    1. Boiler (power generation)
    2. Cogeneration
    3. Combined cycle power plant
    4. Concentrated solar power
    5. Cooling tower (Level 4)
    6. Fossil fuel power station
      1. Coal-fired power station
      2. Gas-fired power plant
    7. Geothermal power (Level 4)
  7. Turbine (Level 4)
    1. Gas turbine (Level 4)
    2. Steam turbine (Level 4)
    3. Wind turbine (Level 4)
  8. Wind power (Level 3)
    1. Windmill (Level 4)

Power storage (12 articles)

  1. Energy storage
  2. Electric battery (Level 3)
    1. Lead–acid battery
    2. Nickel–iron battery
    3. Nickel–metal hydride battery
    4. Lithium-ion battery
    5. Lithium polymer battery
    6. Alkaline battery
    7. Atomic battery
  3. Fuel cell
  4. Pumped-storage hydroelectricity
  5. Solar fuel

Power transmission (62 articles)

See also: Electromagnetism and Electromagnetism

  1. AC power plugs and sockets
  2. Electric power transmission (Level 4)
  3. Electric power distribution (Level 4)
  4. Electrical grid (Level 4)
    1. Three-phase electric power
    2. Virtual power plant
  5. Electrical wiring (Level 4)
    1. Electrical cable (Level 4)
  6. Mains electricity

Concepts (23 articles)

  1. Availability factor
  2. Automatic generation control
  3. Backfeeding
  4. Base load
  5. Capacity factor
  6. Demand factor
  7. Droop speed control
  8. Energy demand management
  9. Energy return on investment
  10. Electrical fault
  11. Grid energy storage
  12. Grid code
  13. Home energy storage
  14. Load factor (electrical)
  15. Load-following power plant
  16. Merit order
  17. Nameplate capacity
  18. Peak demand
  19. Electric power quality
  20. Power-flow study
  21. Repowering
  22. Utility frequency
  23. Variable renewable energy

Electricity transmission and distribution (20 articles)

  1. Demand response
  2. Distributed generation
  3. Dynamic demand (electric power)
  4. Electrical busbar system
  5. Electric power system
  6. Interconnector
  7. High-voltage direct current
  8. High-voltage shore connection
  9. Load management
    1. Electricity market
  10. Mains electricity by country
  11. Overhead power line
  12. Smart grid
  13. Electrical substation
  14. Super grid
  15. Transmission system operator
  16. Transmission tower
  17. Utility pole
    1. Overhead cable
  18. Wide area synchronous grid

Electrical protective devices (10 articles)

  1. Arc-fault circuit interrupter
  2. Circuit breaker (Level 4)
  3. Earth-leakage circuit breaker
  4. Fuse (electrical) (Level 4)
  5. Lightning rod
  6. Residual-current device
  7. Power system protection
  8. Protective relay
  9. Numerical relay
  10. Sulfur hexafluoride circuit breaker

Specific energy structure (3 articles)

See "Dams" section in "Specific infrastructure" for hydroelectric power plants

  1. Synchronous grid of Continental Europe
  2. Eastern Interconnection
  3. Western Interconnection

Industry (199 articles)

See also: "Industry" in Business and economics (Level 4)

General (17 articles)

  1. Factory (Level 4)
    1. Assembly line (Level 4)
    2. Automation (Level 4)
    3. Conveyor system
      1. Conveyor belt
    4. Industrial robot (Level 4)
    5. Interchangeable parts (Level 4)
    6. Mass production (Level 4)
    7. Mechanization (Level 4)
  2. Pelletizing
  3. Standardization (Level 4)
  4. Waste (Level 4)
    1. Incineration
    2. Landfill (Level 4)
    3. Recycling (Level 4)
    4. Waste management (Level 4)
  5. 3D printing

Food, water and health (26 articles)

  1. Air purifier
    1. Air filter
      1. HEPA
    2. Catalytic converter
    3. Respirator
      1. Gas mask
    4. Scrubber
  2. Bleach (Level 4)
  3. Desalination (Level 4)
  4. Detergent (Level 4)
  5. Laundry (Level 4)
  6. Food storage
    1. Pasteurization (Level 4)
  7. Sanitation (Level 3)
    1. Sanitary sewer (Level 4)
    2. Sewage treatment (Level 4)
    3. Water purification (Level 4)
    4. Manhole
  8. Soap (Level 4)
  9. Sterilization (microbiology)
  10. Water supply network (Level 4)
    1. Aqueduct (water supply) (Level 4)
    2. Qanat (Level 4)
    3. Pumping station (Level 4)
    4. Water tower (Level 4)
    5. Well (Level 4)

Materials (39 articles)

  1. Abrasive (Level 4)
  2. BARS apparatus
  3. Ceramic (Level 4)
    1. Pottery (Level 3)
    2. Porcelain (Level 4)
    3. Kiln
  4. Chemical vapor deposition
  5. Glass (Level 3)
    1. Borosilicate glass
    2. Float glass
    3. Fused quartz
    4. Glassblowing
    5. Glass fiber
      1. Glass wool
    6. Safety glass
    7. Soda–lime glass
  6. Leather (Level 4)
    1. Artificial leather
    2. Deliming
    3. Hide (skin)
    4. Liming (leather processing)
    5. Parchment (Level 4)
      1. Vellum
    6. Suede
    7. Tanning (leather)
  7. Mineral wool
  8. Natural rubber (Level 3)
    1. Vulcanization
  9. Paper (Level 3)
    1. Cardboard
    2. Papermaking
      1. Pulp (paper)
      2. Sizing
    3. Papyrus (Level 4)
    4. Tissue paper
  10. Plastic (Level 3)
    1. Carbon-fiber-reinforced polymers
    2. Fiberglass
    3. Injection moulding

Chemicals (8 articles)

  1. Adhesive (Level 4)
  2. Chemical plant (Level 4)
  3. Composite material (Level 4)
  4. Explosive (Level 3)
    1. Dynamite (Level 4)
    2. Fireworks (Level 4)
  5. Lubricant
  6. Petrochemical (Level 4)

Metallurgy (50 articles)

  1. Metallurgy (Level 3)
    1. Smelting (Level 4)
      1. Blast furnace
      2. Crucible
      3. Electric arc furnace
      4. Induction furnace
  2. Extractive metallurgy
    1. Drywasher
    2. Gold dredge
    3. Mineral processing
      1. Crusher
      2. Mechanical screening
      3. Mineral jig
      4. Spiral separator
      5. Stamp mill
      6. Trommel screen
    4. Rocker box
  3. Metalworking (Level 4)
    1. Anvil
    2. Bellows
    3. Bending (metalworking)
    4. Metal casting
      1. Die casting (Level 4)
      2. Lost-wax casting
      3. Sand casting
    5. Drawing (manufacturing)
      1. Wire (Level 4)
    6. Electrical discharge machining
    7. Extrusion (Level 4)
    8. Forge
    9. Forging (Level 4)
      1. Power hammer
    10. Grinding (abrasive cutting)
    11. Heat treating (Level 4)
    12. Laser cutting (Level 4)
    13. Machining
    14. Metal fabrication
    15. Plating
      1. Anodizing
      2. Electroplating
      3. Powder coating
    16. Precipitation hardening
    17. Quenching
    18. Rolling (metalworking) (Level 4)
    19. Sheet metal
    20. Sintering
    21. Soldering (Level 4)
    22. Steelmaking (Level 4)
    23. Welding (Level 4)
    24. Work hardening

Textiles (59 articles)

  1. Textile (Level 3)
    1. Carding

Fabrics and fibers (19 articles)

  1. Canvas (Level 4)
  2. Carbon fibers
  3. Cotton (Level 3)
    1. Chino cloth
    2. Denim
    3. Muslin
  4. Felt (Level 4)
  5. Flannel
  6. Fiber (Level 4)
  7. Jute (Level 4)
  8. Lace (Level 4)
  9. Linen (Level 4)
  10. Polyester (Level 4)
  11. Silk (Level 4)
  12. Thread (yarn) (Level 4)
  13. Wool (Level 4)
    1. Cashmere wool
    2. Tweed
  14. Yarn (Level 4)

Other techniques (10 articles)

  1. Basket weaving (Level 4)
  2. Crochet (Level 4)
  3. Dyeing (Level 4)
    1. Dye (Level 4)
  4. Embroidery (Level 4)
  5. Knitting (Level 4)
  6. Macramé (Level 4)
  7. Textile printing
  8. Quilting (Level 4)
  9. Sewing (Level 4)

Spinning (13 articles)

  1. Hand spinning (Level 4)
    1. Distaff
    2. Spindle (textiles)
  2. DREF friction spinning
  3. Open-end spinning
  4. Spinning (polymers)
    1. Spinneret (polymers)
  5. Ring spinning
  6. Spinning frame
    1. Water frame
  7. Spinning jenny
  8. Spinning mule
  9. Spinning wheel

Weaving (15 articles)

  1. Loom (Level 4)
    1. Jacquard machine
    2. Pirn
    3. Power loom
    4. Shuttle (weaving)
      1. Flying shuttle
  2. Weaving (Level 4)
    1. Brocade
    2. Damask
    3. Plain weave
    4. Satin
    5. Songket
    6. Tapestry (Level 4)
    7. Twill
    8. Warp and weft

Infrastructure (240 articles)

See also Arts: Architecture

Basics (2 articles)

  1. Building (Level 4)
  2. Infrastructure (Level 3)

Building materials (42 articles)

  1. Brick (Level 4)
    1. Fire brick
  2. Cement (Level 4)
    1. Bitumen
    2. Portland cement
  3. Concrete (Level 3)
    1. Asphalt concrete
    2. Concrete slab
    3. Precast concrete
    4. Prestressed concrete
    5. Ready-mix concrete
    6. Reinforced concrete
      1. Rebar
    7. Roman concrete
    8. Shotcrete
  4. Masonry (Level 3)
    1. Brickwork
    2. Stonemasonry
  5. Quarry (Level 4)
  6. Scaffolding (Level 4)
  7. Adobe
  8. Construction aggregate
  9. Clapboard
  10. Mortar (masonry)
  11. Lath and plaster
    1. Lath
    2. Plaster
  12. Drywall
  13. Rammed earth
  14. Roof shingle
  15. Siding (construction)
  16. Stone slab
  17. Tile
  18. Wattle and daub
  19. Wood (Level 3)
    1. Engineered wood
      1. Wood–plastic composite
    2. Lumber (Level 4)
      1. Sawmill
    3. Wood drying
    4. Woodworking (Level 4)
      1. Carpentry (Level 4)

Environmental remediation (10 articles)

  1. Environmental remediation
    1. Bioremediation
      1. Bioaugmentation
      2. Biostimulation
      3. Phytoremediation
    2. Groundwater remediation
    3. In situ chemical oxidation
    4. Soil vapor extraction
    5. Remediation of contaminated sites with cement
    6. Thermal desorption

Infrastructure by type (93 articles)

Architectural elements (20 articles)

  1. Arch (Level 4)
  2. Buttress
    1. Flying buttress
  3. Ceiling (Level 4)
  4. Column (Level 4)
  5. Dome (Level 4)
  6. Door (Level 4)
  7. Elevator (Level 4)
  8. Façade (Level 4)
  9. Floor (Level 4)
  10. Foundation (engineering) (Level 4)
  11. Ladder (Level 4)
  12. Lighting (Level 4)
  13. Pier (architecture)
  14. Roof (Level 4)
  15. Room (Level 4)
  16. Stairs (Level 4)
  17. Vault (architecture)
  18. Wall (Level 4)
  19. Window (Level 4)

Coastal infrastructure (10 articles)

  1. Dock (Level 4)
    1. Dry dock
    2. Marina
  2. Harbor (Level 4)
  3. Lighthouse (Level 4)
  4. Pier (Level 4)
    1. Passenger terminal (maritime)
  5. Port (Level 4)
    1. Container port
  6. Seawall

Ceremonial buildings (2 articles)

  1. Pagoda (Level 4)
  2. Pyramid (Level 4)

Commercial buildings (2 articles)

  1. Office (Level 4)
  2. Warehouse (Level 4)

Mixed-use buildings (3 articles)

  1. Tower block (Level 4)
  2. Skyscraper (Level 4)
  3. Tower (Level 4)

Residential buildings and housing units (10 articles)

  1. Apartment (Level 4)
  2. House (Level 4)
    1. Hut (Level 4)
    2. Igloo (Level 4)
    3. Palace (Level 4)
    4. Villa (Level 4)
  3. Hotel (Level 4)
    1. Inn
    2. Motel
  4. Hostel

Rooms and spaces (18 articles)

  1. Attic
  2. Balcony
  3. Basement
  4. Bathroom (Level 4)
  5. Bedroom (Level 4)
  6. Courtyard
  7. Dining room
  8. Garage (residential) (Level 4)
  9. Hall
  10. Kitchen (Level 4)
  11. Laundry room
  12. Living room
  13. Lobby (room)
  14. Porch
  15. Patio
  16. Sauna (Level 4)
  17. Study (room)
  18. Sunroom

Portable buildings and shelters (2 articles)

  1. Tent (Level 4)
  2. Yurt

Earthworks (3 articles)

  1. Earthworks (engineering)
    1. Trench
  2. Undergrounding

Hydraulic infrastructure (11 articles)

  1. Cistern
  2. Dam (Level 3)
    1. Caisson (engineering)
    2. List of dams and reservoirs
  3. Drainage (Level 4)
    1. Sluice
  4. Dredging
  5. Flood control (Level 4)
    1. Flood control in the Netherlands (Level 4)
  6. Levee (Level 4)
  7. Reservoir (Level 4)

Transport infrastructure (12 articles)

See also #Transportation section

  1. Bridge (Level 3)
    1. Cantilever bridge
    2. Drawbridge
    3. Flying junction
    4. Pontoon bridge
    5. Suspension bridge
    6. Viaduct
  2. Tunnel (Level 4)
    1. Underwater tunnel
    2. Tunnel construction
      1. New Austrian tunneling method
      2. Tunnel boring machine

Specific infrastructure (93 articles)

See "Transportation" and "Energy" section for infrastructure in respective discipline

Dams (31 articles)

  1. Aswan Dam (Level 4)
  2. Grand Coulee Dam
  3. Hoover Dam (Level 4)
  4. Itaipu Dam (Level 4)
  5. Tarbela Dam
  6. Three Gorges Dam (Level 4)
  7. Akosombo Dam
  8. Atatürk Dam
  9. Boegoeberg Dam
  10. Bratsk Hydroelectric Power Station
  11. Cahora Bassa
  12. Cofferdam
  13. New Croton Dam
  14. Delta Works
  15. Tabqa Dam
  16. Fengman Dam
  17. Fort Peck Dam
  18. Grande Dixence Dam
  19. Guri Dam
  20. Enguri Dam
  21. Kariba Dam
  22. Lomaum Dam
  23. Mangla Dam
  24. Nurek Dam
  25. Oroville Dam
  26. Rogun Dam
  27. Ruacana Hydroelectric Power Station
  28. Sennar Dam
  29. Sup'ung Dam
  30. Tibi Dam
  31. Vajont Dam

Bridges (52 articles)

  1. Akashi Kaikyo Bridge (Level 4)
  2. Alcántara Bridge
  3. Arrábida Bridge
  4. Arthur Kill Bridge
  5. Astoria–Megler Bridge
  6. Auckland Harbour Bridge
  7. Banpo Bridge
  8. Bosphorus Bridge
  9. Bridge of Sighs
  10. Bridge of the Americas
  11. Britannia Bridge
  12. Brooklyn Bridge (Level 4)
  13. Charles Bridge
  14. Chengyang Bridge
  15. Confederation Bridge
  16. Danyang–Kunshan Grand Bridge
  17. El Ferdan Railway Bridge
  18. Forth Bridge
  19. Gateshead Millennium Bridge
  20. George Washington Bridge
  21. Golden Gate Bridge (Level 4)
  22. Great Belt Bridge
  23. Great Seto Bridge
  24. Humber Bridge
  25. Qingdao Jiaozhou Bay Bridge
  26. Kapellbrücke
  27. London Bridge (Level 4)
  28. Mackinac Bridge
  29. Manhattan Bridge
  30. Mehmed Paša Sokolović Bridge
  31. Menai Bridge
  32. Millau Viaduct
  33. Minneapolis Skyway System
  34. Pont Alexandre III
  35. Pont de la Concorde (Paris)
  36. Pont du Gard
  37. Pont Neuf
  38. Ponte Sant'Angelo
  39. Ponte Vecchio
  40. Rainbow Bridge (Niagara Falls)
  41. Rainbow Bridge (Tokyo)
  42. Rialto Bridge
  43. San Francisco–Oakland Bay Bridge
  44. Si-o-se-pol
  45. Stari Most
  46. Sydney Harbour Bridge
  47. Tacoma Narrows Bridge
  48. The Iron Bridge
  49. Tower Bridge
  50. Trajan's Bridge
  51. Vasco da Gama Bridge
  52. Verrazzano-Narrows Bridge

Tunnels (3 articles)

  1. Channel Tunnel (Level 4)
  2. Gotthard Base Tunnel
  3. Seikan Tunnel

Multi-modal crossings (5 articles)

  1. Bering Strait crossing
  2. Chesapeake Bay Bridge–Tunnel
  3. Hong Kong–Zhuhai–Macau Bridge
  4. Tokyo Bay Aqua-Line
  5. Øresund Bridge

Others (2 articles)

  1. Multilevel streets in Chicago
  2. List of international submarine communications cables

Machinery and tools (282 articles)

General (10 articles)

  1. Machine (Level 4)
  2. MEMS
    1. Micromachinery
    2. Nanoelectromechanical systems
  3. Robotics (Level 3)
    1. Android (robot)
    2. Automaton
    3. Robot (Level 4)
    4. Robotic arm
    5. Leg mechanism

Engines (11 articles)

  1. Engine (Level 3)
    1. Electric motor (Level 3)
    2. Internal combustion engine (Level 3)
      1. Diesel engine (Level 4)
      2. Petrol engine
      3. Reciprocating engine
        1. Four-stroke engine (Level 4)
        2. Two-stroke engine
      4. Pistonless rotary engine
        1. Wankel engine
    3. Steam engine (Level 3)

Hydraulics and pneumatics (25 articles)

  1. Hydraulics
    1. Hydraulic cylinder
    2. Hydraulic machinery
    3. Hydraulic motor
    4. Hydraulic manifold
    5. Pump
      1. Hydraulic ram
    6. Siphon (Level 4)
  2. Pipe (fluid conveyance) (Level 4)
    1. Gasket (Level 4)
    2. Valve (Level 4)
  3. Plumbing (Level 4)
    1. Bidet
    2. Sink (Level 4)
    3. Toilet (Level 4)
      1. Flush toilet
      2. Squat toilet
      3. Toilet seat
      4. Urinal
  4. Pneumatics
    1. Compressor
    2. Jackhammer
    3. Nail gun
    4. Rivet gun
    5. Vacuum pump

Machinery (63 articles)

Farm and garden machinery (16 articles)

  1. Baler
  2. Chainsaw (Level 4)
  3. Combine harvester (Level 4)
  4. Corn harvester
  5. Cotton gin (Level 4)
  6. Cotton picker
  7. Cultivator (Level 4)
  8. Irrigation sprinkler (Level 4)
  9. Lawn mower (Level 4)
  10. Planter (farm implement)
  11. Reaper
  12. Reaper-binder
  13. Seed drill
  14. Swather
  15. Threshing machine
  16. Transplanter

Household appliances (35 articles)

  1. Home appliance (Level 4)
  2. Major appliance
  3. Barbecue grill
  4. Blender
  5. Clothes dryer (Level 4)
  6. Coffeemaker
  7. Dishwasher (Level 4)
  8. Furnace (central heating) (Level 4)
  9. Hair dryer
  10. Hair iron
  11. Humidifier
  12. Ironing (Level 4)
  13. Juicer
  14. Lock and key (Level 4)
    1. Dead bolt
    2. Disc tumbler lock
    3. Electronic lock
    4. Lever tumbler lock
    5. Pin tumbler lock
    6. Skeleton key
  15. Microwave oven (Level 4)
    1. Cavity magnetron (Level 4)
  16. Mixer (appliance)
  17. Oven (Level 3)
    1. Convection oven
  18. Refrigerator (Level 4)
  19. Rice cooker
  20. Sewing machine (Level 4)
  21. Slow cooker
  22. Stove (Level 4)
    1. Electric stove
  23. Vacuum cleaner (Level 4)
  24. Washing machine (Level 4)
  25. Water dispenser
  26. Water heating

Industrial machinery (12 articles)

  1. Centrifuge (Level 4)
    1. Ultracentrifuge
  2. Crane (machine) (Level 4)
  3. Forklift
  4. Mill (grinding)
  5. Machine tool
    1. Lathe (Level 4)
    2. Machine press (Level 4)
    3. Milling (machining)
    4. Numerical control
  6. Potter's wheel (Level 4)
  7. Trip hammer

Mechanisms (63 articles)

  1. Mechanism (engineering)

Flexible components (16 articles)

  1. Belt (mechanical)
  2. Chain (Level 4)
  3. Net (device)
    1. Mesh
      1. Sieve
  4. Rope (Level 4)
    1. Knot (Level 4)
      1. List of knots
      2. Bowline
      3. Double fisherman's knot
      4. Figure-eight knot
    2. Nautical cable
    3. Wire rope
      1. Bowden cable
      2. Flexible shaft
  5. Spring (device) (Level 4)

Rigid components (21 articles)

  1. Blade
  2. Cam
  3. Fastener (Level 4)
    1. Nail (fastener) (Level 4)
    2. Nut (hardware) (Level 4)
    3. Rivet (Level 4)
    4. Screw
    5. Washer (hardware) (Level 4)
  4. Gear (Level 4)
  5. Hook
  6. Piston
  7. Simple machine (Level 3)
    1. Inclined plane (Level 4)
    2. Lever (Level 4)
    3. Pulley (Level 4)
      1. Block and tackle
    4. Screw (simple machine) (Level 4)
      1. Propeller
    5. Wedge (Level 4)
    6. Wheel (Level 3)
      1. Flywheel

Simple mechanisms (25 articles)

  1. Kinematic pair
    1. Ball joint
    2. Bearing (mechanical) (Level 4)
    3. Cam follower
      1. Tappet
    4. Hinge
    5. Rack and pinion
    6. Ratchet (device)
    7. Rod end bearing
    8. Wheel and axle (Level 4)
      1. Axle (Level 4)
  2. Linkage (mechanical)
    1. Clutch (Level 4)
    2. Differential (mechanical device)
    3. Epicyclic gearing
    4. Escapement
    5. Four-bar linkage
    6. Gimbal
    7. Pantograph
    8. Whippletree (mechanism)
  3. Shock absorber
    1. Dashpot
  4. Winch
    1. Capstan (nautical)
    2. Windlass

Tools (110 articles)

  1. Tool (Level 2)
  2. Lifting equipment
    1. Jack (device)

Agricultural tools (15 articles)

  1. Archimedes' screw (Level 4)
  2. Flail
  3. Grain cradle
  4. Harrow (tool) (Level 4)
  5. Hoe (tool) (Level 4)
  6. Machete (Level 4)
  7. Mattock
  8. Pitchfork
  9. Plough (Level 4)
  10. Rake (tool) (Level 4)
  11. Roller (agricultural tool)
  12. Scythe
  13. Sickle (Level 4)
  14. Shadoof
  15. Shovel (Level 4)

Artist's and drafting tools (19 articles)

  1. Compass (drawing tool)
  2. Drafting machine
  3. Drawing board
  4. Easel
  5. Eraser
  6. French curve
  7. Ink (Level 4)
  8. Modelling clay (Level 4)
  9. Paint (Level 4)
    1. Acrylic paint
    2. Enamel paint
    3. Varnish
  10. Brush (Level 4)
  11. Pastel (Level 4)
  12. Pencil (Level 4)
  13. Pencil sharpener
  14. Pigment (Level 4)
  15. Pen (Level 4)
  16. T-square

Containers (18 articles)

  1. Container (Level 4)
  2. Aluminum can
  3. Bag
    1. Paper bag
    2. Plastic bag
  4. Barrel
  5. Basket
  6. Bottle
    1. Water bottle
  7. Box
    1. Coffin
    2. Crate
    3. Wooden box
  8. Envelope
  9. Intermodal container
  10. Paper cup
  11. Pressure vessel
  12. Steel and tin cans

Hand tools (15 articles)

  1. Adze
  2. Axe (Level 4)
  3. Chalk line
  4. Chisel (Level 4)
  5. Clamp (tool) (Level 4)
  6. Crowbar
  7. Drilling (Level 4)
  8. Hammer (Level 4)
  9. Hook (hand tool)
  10. Plane (tool) (Level 4)
  11. Pliers
  12. Saw (Level 4)
  13. Scissors (Level 4)
  14. Screwdriver
  15. Wrench

Measuring instruments (20 articles)

  1. Instrumentation (Level 4)
    1. Barometer (Level 4)
    2. Calipers (Level 4)
    3. Feeler gauge
    4. Ruler (Level 4)
      1. Meterstick
      2. Tape measure
    5. Photometer (Level 4)
    6. Spectrometer (Level 4)
      1. Optical spectrometer
    7. Thermometer (Level 4)
    8. Astrolabe
    9. Breathalyzer
    10. Calorimeter
    11. Geiger counter
    12. Odometer
    13. Seismometer
    14. Speedometer
    15. Torque wrench
    16. Vernier scale

Surveying tools (20 articles)

  1. Alidade
  2. Circumferentor
  3. Graphometer
  4. Gunter's chain
  5. Laser rangefinder
    1. Lidar
  6. Level (optical instrument)
    1. Inclinometer
      1. Topographic Abney level
    2. Level staff
    3. Plumb bob
    4. Spirit level
    5. Tiltmeter
  7. Plane table
  8. Reticle
  9. Stadimeter
    1. Stadia mark
  10. Surveyor's wheel
  11. Theodolite (Level 4)
    1. Total station

Medical technology (17 articles)

Diagnostic technologies (4 articles)

  1. DNA profiling (Level 4)
  2. Electrocardiography (Level 4)
  3. Electroencephalography
  4. Endoscopy (Level 4)

Imaging (6 articles)

  1. Medical imaging (Level 3)
  2. CT scan
  3. Magnetic resonance imaging (Level 4)
  4. Medical ultrasound (Level 4)
  5. Positron emission tomography
  6. Radiography (Level 4)

Devices (3 articles)

  1. Artificial organ (Level 4)
  2. Prosthesis (Level 4)
  3. Wheelchair (Level 4)

Techniques (2 articles)

  1. Cardiopulmonary bypass (Level 4)
  2. Dialysis (chemistry) (Level 4)

Transport (2 articles)

  1. Ambulance (Level 4)
  2. Air medical services

Military technology (302 articles)

General (8 articles)

  1. Weapon (Level 3)
  2. Military technology (Level 4)
  3. Booby trap
    1. Punji stick
    2. Trou de loup
  4. Siege engine
    1. Battering ram (Level 4)
    2. Siege tower

Countermeasures (27 articles)

  1. Stealth technology (Level 4)
  2. Missile defense

Armour (11 articles)

  1. Armour (Level 3)
    1. Body armor
      1. Bulletproof vest (Level 4)
      2. Chain mail (Level 4)
      3. Plate armour (Level 4)
    2. Vehicle armour
      1. Reactive armour
  2. Helmet (Level 4)
    1. Combat helmet
  3. Shield (Level 4)
    1. Scutum

Fortification (14 articles)

  1. Fortification (Level 3)
    1. Bastion fort
      1. Glacis
      2. Ravelin
      3. Tenaille
    2. Castle (Level 4)
      1. Motte-and-bailey castle
      2. Bastion
      3. Curtain wall (fortification)
      4. Gatehouse
      5. Keep
    3. Defensive wall (Level 4)
      1. Palisade
      2. Rampart (fortification)

Melee weapons (40 articles)

  1. Melee weapon
  2. Battle axe (Level 4)
  3. Brass knuckles
  4. Club (weapon) (Level 4)
    1. Baton (law enforcement)
    2. Mace (bludgeon)
    3. War hammer
  5. Flail (weapon)
    1. Nunchaku

Knives (11 articles)

  1. Assisted-opening knife
    1. Switchblade
  2. Bayonet (Level 4)
  3. Knife (Level 3)
  4. Dagger (Level 4)
  5. Fighting knife
    1. Bowie knife
  6. Hunting knife
  7. Pocketknife
    1. Swiss Army knife
  8. Throwing knife

Polearms (8 articles)

  1. Polearm
  2. Dagger-axe
    1. Ji (polearm)
  3. Halberd
  4. Naginata
  5. Partisan (weapon)
  6. Spear (Level 4)
    1. Pike (weapon)

Swords (12 articles)

  1. Sword (Level 4)
  2. Claymore
  3. Cutlass
  4. Dao (Chinese sword)
  5. Gladius
  6. Katana (Level 4)
  7. Longsword
  8. Rapier (Level 4)
  9. Sabre
  10. Scimitar
  11. Talwar
  12. Wakizashi

Ranged weapons (107 articles)

  1. Ranged weapon
  2. Boomerang (Level 4)
  3. Javelin
    1. Spear-thrower
  4. Shuriken
  5. Sling (weapon) (Level 4)
  6. Slingshot

Archery (11 articles)

  1. Bow and arrow (Level 3)
    1. Compound bow
    2. Longbow
    3. Recurve bow
  2. Arrow
    1. Arrowhead
    2. Fletching
  3. Bowstring
  4. Crossbow (Level 4)
    1. Repeating crossbow
  5. Quiver

Artillery (13 articles)

  1. Artillery (Level 4)
  2. Cannon (Level 4)
    1. Field gun
    2. Howitzer
    3. Limbers and caissons
    4. Mortar (weapon) (Level 4)
  3. Catapult (Level 4)
    1. Ballista (Level 4)
      1. Polybolos
    2. Mangonel
    3. Onager (weapon)
    4. Trebuchet
  4. Railgun

Firearms (65 articles)

  1. Firearm (Level 3)
    1. Fire lance
    2. Hand cannon
    3. Gun
  2. Handgun (Level 4)
    1. Revolver
    2. Pistol
  3. Long gun
    1. Arquebus
    2. Musket (Level 4)
    3. Rifle (Level 4)
      1. Assault rifle (Level 4)
      2. Sniper rifle
    4. Shotgun (Level 4)
    5. Submachine gun
  4. Machine gun (Level 4)
  5. Autocannon
    1. Rotary cannon

Ammunition (15 articles)

  1. Ammunition (Level 4)
    1. Ammunition box
  2. Gunpowder (Level 3)
    1. Powder keg
    2. Smokeless powder
  3. Bullet
    1. Armor-piercing bullet
    2. Hollow-point bullet
    3. Tracer ammunition
  4. Flechette
  5. Cartridge (firearms)
    1. Sabot (firearms)
  6. Shotgun shell
    1. Shot (pellet)
  7. Shotgun slug

Mechanisms (19 articles)

  1. Breechloader
    1. Action (firearms)
      1. Automatic firearm
      2. Bolt action
      3. Burst mode (weapons)
      4. Repeating firearm
      5. Selective fire
      6. Semi-automatic firearm
    2. Firing pin
    3. Magazine (firearms)
  2. Gun barrel
    1. Multiple-barrel firearm
    2. Rifling
  3. Muzzleloader
    1. Flintlock
    2. Matchlock
    3. Percussion cap
    4. Wheellock
  4. Trigger (firearms)

Specific cartridges (2 articles)

  1. 9×19mm Parabellum
  2. 5.56×45mm NATO

Specific firearms (11 articles)

  1. AK-47
  2. AR-15–style rifle
  3. Chassepot
  4. Dreyse needle gun
  5. Gatling gun
  6. Glock
  7. IWI Tavor
  8. M134 Minigun
  9. M4 carbine
  10. M16 rifle
  11. M1911 pistol

Missiles (11 articles)

  1. Missile (Level 4)
    1. Air-to-air missile
    2. Anti-tank guided missile
    3. Cruise missile
    4. Intercontinental ballistic missile
    5. Rocket-propelled grenade
    6. Surface-to-air missile
      1. Man-portable air-defense system
  2. Missile guidance
  3. Multiple rocket launcher
  4. Warhead

Explosive weapons (15 articles)

  1. Bomb (Level 4)
    1. Improvised explosive device (Level 4)
      1. Car bomb
    2. Detonator
    3. Fuze
      1. Contact fuze
      2. Proximity fuze
  2. Cluster munition (Level 4)
  3. Grenade (Level 4)
  4. Land mine (Level 4)
  5. Plastic explosive
  6. Shaped charge
    1. Explosively formed penetrator
    2. High-explosive anti-tank
  7. Thermobaric weapon

Incendiary weapons (5 articles)

  1. Greek fire
  2. Flamethrower
  3. Molotov cocktail
  4. Napalm (Level 4)
  5. White phosphorus munitions

Maneuver (9 articles)

  1. Horses in warfare (Level 4)
    1. Caltrop
    2. Chariot (Level 4)
  2. Infantry fighting vehicle
    1. Armoured personnel carrier
    2. Technical (vehicle)
  3. Tank (Level 4)
    1. Main battle tank
  4. War elephant (Level 4)

Military aviation (45 articles)

  1. Military aviation
  2. Military aircraft (Level 4)
    1. Military glider
    2. Military helicopter
  3. Attack aircraft (Level 4)
    1. Gunship
  4. Bomber (Level 4)
    1. Strategic bomber
    2. Heavy bomber
    3. Medium bomber
    4. Interdictor
    5. Penetrator (aircraft)
  5. Fighter aircraft (Level 4)
    1. Air superiority fighter
    2. Interceptor aircraft
    3. Fighter-bomber
    4. Strike fighter
  6. Electronic-warfare aircraft
  7. Maritime patrol aircraft
  8. Multirole combat aircraft
  9. Military transport aircraft
  10. Airborne early warning and control
  11. Reconnaissance aircraft
  12. Surveillance aircraft
  13. Experimental aircraft
  14. Aerial refueling

Specific aircraft (19 articles)

  1. Boeing B-29 Superfortress
    1. Enola Gay
  2. Boeing B-52 Stratofortress
  3. Dassault Rafale
  4. Embraer EMB 314 Super Tucano
  5. Eurofighter Typhoon
  6. Fairchild Republic A-10 Thunderbolt II
  7. General Dynamics F-16 Fighting Falcon
  8. Lockheed C-130 Hercules
  9. Lockheed SR-71 Blackbird
  10. Lockheed Martin F-22 Raptor
  11. Lockheed Martin F-35 Lightning II
  12. McDonnell Douglas F-15 Eagle
  13. McDonnell Douglas F/A-18 Hornet
  14. Mikoyan-Gurevich MiG-21
  15. North American P-51 Mustang
  16. Northrop Grumman B-2 Spirit
  17. Panavia Tornado
  18. Rockwell B-1 Lancer

Naval warfare (20 articles)

  1. Warship (Level 4)
    1. Aircraft carrier (Level 4)
    2. Battleship (Level 4)
      1. Dreadnought
    3. Corvette
    4. Cruiser
    5. Destroyer
    6. Frigate
    7. Galleon
    8. Galley (Level 4)
      1. Trireme
    9. Gunboat
    10. Ironclad warship
    11. Ship of the line (Level 4)
  2. Submarine (Level 4)
  3. Boom (navigational barrier)
    1. Anti-submarine net
  4. Depth charge
  5. Naval mine (Level 4)
  6. Torpedo (Level 4)

Less-lethal weapons (14 articles)

  1. Non-lethal weapon
  2. Active Denial System
  3. Baton round
    1. Bean bag round
    2. Plastic bullet
    3. Rubber bullet
    4. Sponge grenade
  4. Sonic weapon
  5. Stun grenade
  6. Taser
  7. Tear gas
    1. CS gas
    2. Pepper spray
  8. Water cannon

Weapon of mass destruction (12 articles)

  1. Weapon of mass destruction (Level 4)
  2. Biological warfare (Level 4)
    1. Entomological warfare
  3. Chemical weapon (Level 4)
    1. Blister agent
    2. Blood agent
    3. Nerve agent
  4. Dirty bomb
  5. Nuclear weapon (Level 3)
    1. Thermonuclear weapon (Level 4)
    2. Nuclear weapon design
    3. Nuclear proliferation

Navigation and timekeeping (88 articles)

For units of time (hour, day, etc.), see Physical sciences – Measurement. For maps and cartography, see Geography – Physical geography.

Navigation (23 articles)

  1. Navigation (Level 3)
  2. Compass (Level 3)
  3. Cardinal direction (Level 4)
    1. North
    2. South
    3. East
    4. West
  4. Celestial navigation (Level 4)
    1. Backstaff
    2. Jacob's staff
    3. Octant (instrument)
    4. Quadrant (instrument)
    5. Sextant (Level 4)
  5. Dead reckoning (Level 4)
  6. Gyroscope (Level 4)
  7. Satellite navigation (Level 4)
    1. BeiDou
    2. Galileo (satellite navigation)
    3. Global Positioning System (Level 4)
    4. GLONASS
    5. Satellite navigation device
  8. Radar (Level 3)
  9. Sonar (Level 4)

Timekeeping (65 articles)

  1. Astronomical year numbering
  2. Calendar (Level 3)
  3. Clock (Level 3)
  4. Horology
  5. Leap year (Level 4)
  6. Leap second
  7. Future
  8. Present
  9. Past
  10. Standard time
  11. Timeline
  12. Time standard
    1. Coordinated Universal Time
    2. Greenwich Mean Time
    3. International Atomic Time
  13. Time zone (Level 4)
    1. Daylight saving time (Level 4)

Calendars (12 articles)

  1. Solar calendar
    1. Gregorian calendar (Level 4)
      1. Anno Domini
      2. Common Era
    2. Julian calendar (Level 4)
  2. Lunisolar calendar
    1. Buddhist calendar
    2. Chinese calendar (Level 4)
    3. Hindu calendar
  3. Lunar calendar
    1. Hebrew calendar
    2. Islamic calendar (Level 4)

Clocks (16 articles)

  1. 12-hour clock
  2. 24-hour clock
  3. Alarm clock
  4. Atomic clock (Level 4)
  5. Digital clock
  6. Clock face
  7. Hourglass
  8. Marine chronometer
  9. Pendulum clock
    1. Pendulum (Level 4)
  10. Quartz clock
  11. Sundial (Level 4)
  12. Watch (Level 4)
    1. Pocket watch
    2. Stopwatch
  13. Water clock

Months (12 articles)

  1. January
  2. February
  3. March
  4. April
  5. May
  6. June
  7. July
  8. August
  9. September
  10. October
  11. November
  12. December

Days of the Week (8 articles)

  1. Names of the days of the week
  2. Sunday
  3. Monday
  4. Tuesday
  5. Wednesday
  6. Thursday
  7. Friday
  8. Saturday

Optical technology (57 articles)

Optical components (14 articles)

  1. Lens (Level 3)
    1. Fresnel lens
    2. Thin lens
  2. Anti-reflective coating (Level 4)
  3. Collimator
  4. Diffraction grating (Level 4)
  5. Mirror (Level 4)
    1. One-way mirror
  6. Optical fiber (Level 4)
  7. Optical filter
  8. Optical isolator
  9. Polarizer (Level 4)
  10. Prism (optics) (Level 4)
    1. Pentaprism

Optical instruments (15 articles)

  1. Autocollimator
  2. Binoculars (Level 4)
  3. Glasses (Level 4)
    1. Bifocals
  4. Interferometry (Level 4)
  5. Loupe
  6. Magnifying glass
  7. Microscope (Level 3)
    1. Electron microscope (Level 4)
      1. Scanning electron microscope
      2. Transmission electron microscopy
      3. Scanning tunneling microscope
    2. Optical microscope (Level 4)
  8. Periscope
  9. Projector

Lasers (9 articles)

  1. Laser (Level 3)
    1. Solid-state laser
      1. Ruby laser
      2. Nd:YAG laser
    2. Dye laser
    3. Gas laser
      1. Carbon-dioxide laser
      2. Helium–neon laser
  2. Maser

Photography (19 articles)

  1. Camera (Level 3)
    1. Hidden camera
    2. Instant camera
    3. Rangefinder camera
    4. Single-lens reflex camera
      1. Digital single-lens reflex camera
    5. Twin-lens reflex camera
  2. Holography (Level 4)
  3. Photographic film (Level 4)
    1. Photographic plate
  4. Photography (Level 3)
    1. Digital photography (Level 4)
    2. Fine-art photography (Level 4)
    3. Landscape photography
    4. Portrait photography
    5. Street photography
    6. Exposure (photography)
    7. Flash (photography)
    8. Multi-exposure HDR capture

Astronomical technology (72 articles)

  1. Astronomical catalog
  2. Ephemeris
  3. Star chart
  4. Astronomical Almanac

Telescope (68 articles)

  1. Telescope (Level 3)
  2. Reflecting telescope
    1. Cassegrain reflector
    2. Dobsonian telescope
    3. Gregorian telescope
    4. Newtonian telescope
    5. Ritchey–Chrétien telescope
    6. Schmidt–Cassegrain telescope
  3. Refracting telescope
  4. X-ray telescope
    1. X-ray astronomy detector
  5. Optical telescope (Level 4)
  6. Infrared telescope
  7. Radio telescope (Level 4)
  8. Solar telescope
  9. Space telescope
  10. Astronomical interferometer
    1. Aperture synthesis
  11. Telescope mount
    1. Altazimuth mount
    2. Equatorial mount
  12. Active optics
  13. Adaptive optics
  14. Eyepiece
  15. Astronomical filter
  16. Primary mirror
  17. Gravitational-wave observatory

Space-based observatories (15 articles)

  1. Hubble Space Telescope (Level 4)
  2. Spitzer Space Telescope
  3. Herschel Space Observatory
  4. INTEGRAL
  5. Fermi Gamma-ray Space Telescope
  6. James Webb Space Telescope
  7. Wide-field Infrared Survey Explorer
  8. IRAS
  9. Chandra X-ray Observatory
  10. Kepler
  11. GALEX
  12. Hipparcos
  13. Gaia (spacecraft)
  14. XMM-Newton
  15. ROSAT

Ground-based observatories (26 articles)

  1. Atacama Large Millimeter Array (Level 4)
  2. Mauna Kea Observatories (Level 4)
    1. Subaru Telescope
    2. Thirty Meter Telescope
    3. W. M. Keck Observatory
  3. Gemini Observatory
  4. Five-hundred-meter Aperture Spherical Telescope
  5. LIGO
  6. Virgo interferometer
  7. IceCube Neutrino Observatory
  8. Very Large Telescope
  9. Large Binocular Telescope
  10. Mount Wilson Observatory
  11. Very Large Array
  12. Very Long Baseline Array
  13. Arecibo Observatory
  14. Green Bank Telescope
  15. Effelsberg 100-m Radio Telescope
  16. Low-Frequency Array (LOFAR)
  17. MeerKAT
  18. Square Kilometre Array
  19. Extremely Large Telescope
    1. Giant Magellan Telescope
  20. Wise Observatory
  21. South Pole Telescope
  22. Jodrell Bank Observatory

Space (71 articles)

Basics (16 articles)

  1. Spaceflight (Level 3)
    1. Sub-orbital spaceflight
    2. Orbital spaceflight
  2. Rocket (Level 3)
    1. Launch pad (Level 4)
    2. Launch vehicle (Level 4)
    3. Rocket engine (Level 4)
  3. Satellite (Level 3)
  4. Space station (Level 3)
  5. Astronaut (Level 4)
    1. Space suit
  6. Space capsule (Level 4)
  7. Uncrewed spacecraft
  8. Interstellar travel
  9. Space colonization
  10. Space habitat

Programs and launch sites (16 articles)

  1. NASA (Level 4)
    1. Apollo program (Level 4)
    2. Kennedy Space Center (Level 4)
    3. Project Gemini
    4. Project Mercury
  2. Soviet space program (Level 4)
    1. Baikonur Cosmodrome (Level 4)
    2. Vostok programme
    3. Voskhod programme
    4. Soyuz programme
  3. Roscosmos (Level 4)
  4. European Space Agency (Level 4)
  5. China National Space Administration (Level 4)
  6. ISRO
  7. Israel Space Agency
  8. JAXA

Crewed vehicles (12 articles)

  1. Apollo 11
  2. International Space Station (Level 4)
  3. Mir (Level 4)
  4. Salyut 1
  5. Space Shuttle (Level 4)
    1. Space Shuttle Challenger disaster
    2. Space Shuttle Columbia disaster
  6. Saturn V (Level 4)
  7. Soyuz (spacecraft) (Level 4)
  8. Skylab
  9. Tiangong space station
  10. Vostok 1

Unmanned spacecraft (18 articles)

  1. Sputnik 1 (Level 4)
  2. Sputnik 2
  3. Luna 2
  4. Luna 3
  5. Mariner 2
  6. Luna 9
  7. Voyager program (Level 4)
    1. Voyager 1
    2. Voyager 2
  8. Pioneer program
    1. Pioneer 10
    2. Pioneer 11
  9. New Horizons
  10. Galileo project
  11. Cassini–Huygens
  12. Cosmic Background Explorer
  13. Wilkinson Microwave Anisotropy Probe
  14. MESSENGER

Rovers (9 articles)

  1. Rover (space exploration)
  2. Mars rover
    1. Perseverance (rover)
    2. Curiosity (rover)
    3. Spirit (rover)
    4. Opportunity (rover)
    5. Sojourner (rover)
  3. Lunar rover
    1. Lunokhod 1

Transportation (456 articles)

Basics (18 articles)

  1. Transport (Level 2)
    1. Public transport (Level 4)
    2. Private transport
  2. Travel (Level 4)
  3. Passenger
    1. Intermodal passenger transport
  4. Freight transport (Level 4)
    1. Cargo (Level 4)
  5. Induced demand
  6. Traffic
    1. Traffic collision (Level 4)
    2. Traffic congestion
  7. Vehicle (Level 4)
    1. Motor vehicle
    2. Alternative fuel vehicle
    3. Electric vehicle
    4. Battery electric vehicle
    5. Hybrid vehicle

Ground transport (163 articles)

Concepts of ground transport (22 articles)

  1. Road transport
  2. Breakdown (vehicle)
  3. Charging station
  4. Driving (Level 4)
  5. Filling station (Level 4)
  6. Parking (Level 4)
    1. Parking lot
  7. Service (motor vehicle)
    1. Automobile repair shop
    2. Bus garage
    3. Car wash
    4. Rail yard
  8. Rest area
  9. Tire (Level 4)
  10. Transport hub
    1. Bus station
    2. Bus stop
    3. Bus terminus
    4. Train station (Level 4)
      1. Goods station
      2. Railway platform
    5. Park and ride

Road infrastructure (26 articles)

For bridges and tunnels, see transport infrastructure in #Infrastructure section.

  1. Road (Level 3)
    1. Byway (road)
    2. Dirt road
    3. Highway (Level 4)
      1. Controlled-access highway (Level 4)
      2. Autobahn
      3. Interstate Highway System
    4. Road junction
      1. Interchange (road)
      2. Intersection (road)
        1. Traffic light
        2. Traffic sign
        3. Stack interchange
    5. Toll road
  2. Footpath
  3. Pedestrian crossing
  4. Pedestrian zone
  5. Sidewalk
  6. Trail (Level 4)
  7. Cycling infrastructure
    1. Bicycle boulevard
    2. Bike lane
    3. Bicycle parking rack
    4. Shared-use path
    5. Bicycle-sharing system
    6. Cycle track

Motorized road transport (54 articles)

  1. Auto rickshaw
  2. Bus (Level 4)
    1. Articulated bus
    2. Bus rapid transit
    3. Coach (bus)
    4. Double-decker bus
    5. Minibus
    6. Public transport bus service
    7. School bus
    8. Trolleybus
  3. Car (Level 3)
    1. Convertible
    2. Coupe
    3. Electric car
    4. Grand tourer
    5. Hatchback
    6. Limousine
    7. Luxury car
    8. Microcar
    9. Muscle car
    10. Sedan (automobile)
    11. Sports car
    12. Station wagon
    13. Supercar
    14. T-top
  4. Motorcycle (Level 4)
    1. Chopper (motorcycle)
    2. Minibike
    3. Moped
    4. Rat bike
    5. Scooter (motorcycle)
      1. Kick scooter
      2. Motorized scooter
      3. Scooter-sharing system
    6. Sport bike
  5. Off-road vehicle
    1. All-terrain vehicle
    2. Dune buggy
    3. Snowmobile
  6. Shared transport
    1. Carpool
    2. Demand-responsive transport
  7. Truck (Level 4)
    1. Flatbed truck
    2. Monster truck
    3. Pickup truck
    4. Semi-trailer truck
    5. SUV
  8. Van (Level 4)
    1. Minivan
  9. Vehicle for hire
    1. Motorcycle taxi
    2. Share taxi
    3. Taxi (Level 4)

Rail and cable transport (28 articles)

  1. Rail transport (Level 3)
    1. Railway track (Level 4)
      1. Elevated railway
    2. Railway electrification
  2. Train (Level 4)
    1. Locomotive (Level 4)
      1. Electric locomotive
      2. Diesel locomotive
      3. Steam locomotive (Level 4)
    2. Railroad car
    3. Rolling stock
    4. Passenger train
    5. Rail freight transport
    6. Freight train
  3. Cable transport (Level 4)
    1. Aerial tramway (Level 4)
    2. Cable car (railway)
    3. Funicular
    4. Gondola lift
    5. Ski lift
  4. High-speed rail (Level 4)
  5. Tram (Level 4)
    1. Interurban
    2. Light rail
  6. Rapid transit (Level 4)
    1. Commuter rail
    2. Medium-capacity rail system
      1. Monorail (Level 4)

Animal-powered transport (7 articles)

  1. Carriage (Level 4)
    1. Surrey (carriage)
  2. Cart (Level 4)
  3. Horsecar
  4. Saddle (Level 4)
  5. Stirrup
  6. Stagecoach

Human-powered transport (15 articles)

  1. Bicycle (Level 3)
    1. Bicycle brake
    2. Bicycle gearing
    3. Derailleur
    4. Shifter (bicycle part)
    5. BMX bike
    6. Electric bicycle
    7. Mountain bike
    8. Penny-farthing
    9. Recumbent bicycle
    10. Tandem bicycle
  2. Handcar
  3. Rickshaw (Level 4)
  4. Tricycle
  5. Unicycle

Specific-purpose transportation (10 articles)

For medical transport, see Medical section

  1. Baby transport (Level 4)
  2. Paratransit
  3. Pipeline (Level 4)
  4. Heavy equipment
    1. Bulldozer
    2. Dump truck
    3. Excavator
    4. Road roller
      1. Steamroller
    5. Tractor (Level 4)

Specific automobiles (1 article)

  1. Ford Model T

Naval transport (64 articles)

For military watercraft, see Military technology. For pier and port, see coastal infrastructure.

  1. Ship (Level 3)
    1. Anchor
  2. Watercraft
  3. Buoy
  4. Canal (Level 3)
    1. Lock (water navigation) (Level 4)
  5. Barge (Level 4)
  6. Boat (Level 4)
  7. Canoe (Level 4)
  8. Cargo ship (Level 4)
    1. Container ship
  9. Ferry (Level 4)
  10. Fishing vessel (Level 4)
  11. Hospital ship
  12. Hovercraft (Level 4)
  13. Hydrofoil
  14. Icebreaker
  15. Kayak
  16. Merchant ship (Level 4)
  17. Motor ship
  18. Motorboat
  19. Multihull
    1. Catamaran
  20. Naval architecture
  21. Outrigger
  22. Passenger ship (Level 4)
    1. Cruise ship
    2. Ocean liner
  23. Personal watercraft
  24. Riverboat (Level 4)
  25. Sail (Level 4)
  26. Sailboat
    1. Schooner
    2. Sloop
  27. Sailing ship (Level 4)
    1. Caravel
    2. Clipper
    3. Junk (ship)
  28. Sailing (Level 4)
  29. Scuba set
  30. Snorkel (swimming)
  31. Shipbuilding (Level 4)
  32. Steamboat (Level 4)
  33. Steamship
    1. Paddle steamer
  34. Submersible
    1. Diving bell
    2. Remotely operated underwater vehicle
  35. Tanker (ship) (Level 4)
    1. Oil tanker
  36. Tugboat

Specific piers and ports (13 articles)

  1. Port of Singapore
  2. Port of Ningbo-Zhoushan
  3. Port of Busan
  4. Port of Rotterdam
  5. Port of Jebel Ali
  6. Port of Los Angeles
  7. Port of New York and New Jersey
  8. Port of Port Hedland
  9. Port of Yokohama
  10. Port of Kobe
  11. Port of Hamburg
  12. PortMiami
  13. Port of Barcelona

Aviation (116 articles)

  1. Aviation (Level 4)
    1. Aircraft (Level 3)
      1. Cargo aircraft
      2. Jet aircraft (Level 4)
      3. Line-replaceable unit
      4. Unmanned aerial vehicle (Level 4)
    2. Airport (Level 4)
      1. Airport terminal
      2. Helipad
      3. Runway
    3. Air traffic control (Level 4)
    4. Parachute (Level 4)
    5. Wingsuit flying
  2. Aerostat
    1. Balloon (aeronautics) (Level 4)
      1. Hot air balloon (Level 4)
      2. Gas balloon
    2. Airship (Level 4)
      1. Blimp
      2. Rigid airship
      3. Semi-rigid airship
  3. Fixed-wing aircraft (Level 4)
    1. Airplane (Level 4)
    2. Glider (aircraft) (Level 4)
    3. Ultralight aviation
      1. Powered paragliding
  4. Rotorcraft
    1. Helicopter (Level 4)
  5. Aircraft flight control system
    1. Fly-by-wire
  6. Aircraft engine (Level 4)
    1. Auxiliary power unit
    2. Jet engine (Level 4)
      1. Turbofan
      2. Turbojet
    3. Radial engine
    4. Turboprop
    5. Turboshaft
    6. Thrust reversal
  7. Airframe
    1. Aircraft fairing
    2. Empennage
    3. Fuselage
    4. Landing gear
    5. Wing (Level 4)
      1. Airfoil
      2. Wingtip device
  8. Avionics
    1. ACARS
    2. Airborne collision avoidance system
    3. ARINC 429
    4. Autopilot
    5. FADEC
    6. Flight management system
    7. Flight recorder
    8. Future Air Navigation System
    9. Health and usage monitoring systems
    10. Integrated modular avionics
  9. Cockpit
    1. Flight instruments
    2. Glass cockpit
  10. Flight control surfaces
    1. Aileron
    2. Air brake (aeronautics)
    3. Elevator (aeronautics)
    4. Flap (aeronautics)
    5. Leading-edge slat
    6. Spoiler (aeronautics)
    7. Stabilizer (aeronautics)
    8. Trim tab

Specific aircraft (32 articles)

For military aircraft, see Military technology

  1. Airbus A300
  2. Airbus A320 family
  3. Airbus A330
  4. Airbus A340
  5. Airbus A350
  6. Airbus A380
  7. Antonov An-225 Mriya
  8. Boeing 707
  9. Boeing 727
  10. Boeing 737
  11. Boeing 747
  12. Boeing 757
  13. Boeing 767
  14. Boeing 777
  15. Boeing 787 Dreamliner
  16. De Havilland Canada Dash 8
  17. Cessna 172
  18. Concorde
  19. de Havilland Comet
  20. Douglas DC-3
  21. Douglas DC-6
  22. Douglas DC-8
  23. Embraer E-Jet family
  24. Hughes H-4 Hercules
  25. Ilyushin Il-76
  26. Lockheed Constellation
  27. Lockheed L-1011 TriStar
  28. McDonnell Douglas DC-9
  29. McDonnell Douglas DC-10
  30. Mil Mi-8
  31. Tupolev Tu-154
  32. Wright Flyer

Airports (14 articles)

  1. Hartsfield–Jackson Atlanta International Airport
  2. Beijing Capital International Airport
  3. O'Hare International Airport
  4. Dubai International Airport
  5. Hong Kong International Airport
  6. Heathrow Airport
  7. Los Angeles International Airport
  8. Charles de Gaulle Airport
  9. Haneda Airport
  10. Shanghai Pudong International Airport
  11. Sheremetyevo International Airport
  12. Indira Gandhi International Airport
  13. John F. Kennedy International Airport
  14. Ted Stevens Anchorage International Airport

Specific transportation systems (95 articles)

Ground transportation networks (9 articles)

See Geography/Physical for Maritime transportation network. See Society/Politic and economic for companies that operate transportation networks.

  1. Intercontinental and transoceanic fixed links
  2. Arab Mashreq International Road Network
  3. Asian Highway Network
  4. Trans-African Highway network
  5. Trans-European Transport Network
    1. Trans-European high-speed rail network
  6. EuroVelo
  7. European long-distance paths
  8. Transcontinental railroad

Rapid transit (67 articles)

Africa (1 article)

  1. Cairo Metro

Americas (14 articles)

  1. Caracas Metro
  2. Mexico City Metro
  3. Santiago Metro
  4. TransMilenio
Brazil (2 articles)
  1. Rio de Janeiro Metro
  2. São Paulo Metro
Canada (3 articles)
  1. Montreal Metro
  2. Toronto subway
  3. SkyTrain (Vancouver)
United States (5 articles)
  1. Bay Area Rapid Transit
  2. Chicago "L"
  3. Massachusetts Bay Transportation Authority
  4. New York City Subway (Level 4)
  5. Washington Metro

Asia (24 articles)

  1. Dubai Metro
  2. TransJakarta
  3. Mass Rapid Transit (Singapore)
  4. Taipei Metro
  5. Tehran Metro
China (6 articles)
  1. Beijing Subway
  2. Chongqing Rail Transit
  3. Guangzhou Metro
  4. MTR
  5. Shanghai Metro
  6. Shenzhen Metro
India (5 articles)
  1. Delhi Metro
  2. Hyderabad Metro
  3. Kolkata Metro
  4. Mumbai Metro
  5. Namma Metro
Japan (6 articles)
  1. Hiroshima Electric Railway
  2. Nagoya Municipal Subway
  3. Osaka Metro
  4. Sapporo Municipal Subway
  5. Tokyo Metropolitan Bureau of Transportation
  6. Tokyo Metro
South Korea (2 articles)
  1. Busan Metro
  2. Seoul Metropolitan Subway

Europe (27 articles)

  1. Athens Metro
  2. Brussels Metro
  3. Budapest Metro
  4. Istanbul Metro
  5. Kyiv Metro
  6. Prague Metro
  7. Vienna U-Bahn
France (3 articles)
  1. Lyon Metro
  2. Paris Métro
  3. Réseau Express Régional
Germany (3 articles)
  1. Berlin U-Bahn
  2. Munich U-Bahn
  3. S-Bahn
Italy (2 articles)
  1. Milan Metro
  2. Rome Metro
Netherlands (2 articles)
  1. Amsterdam Metro
  2. Rotterdam Metro
Russia (2 articles)
  1. Moscow Metro
  2. Saint Petersburg Metro
Scandinavia (4 articles)
  1. Copenhagen Metro
  2. Helsinki Metro
  3. Oslo Metro
  4. Stockholm Metro
Spain (2 articles)
  1. Barcelona Metro
  2. Madrid Metro
United Kingdom (2 articles)
  1. Glasgow Subway
  2. London Underground (Level 4)

Oceania (1 article)

  1. Sydney Metro

High-speed rail (13 articles)

  1. Acela
  2. AVE
  3. China Railway High-speed
  4. Eurostar
  5. Frecciarossa
  6. Intercity Express
  7. Korea Train Express
  8. Railjet
  9. Shinkansen (Level 4)
  10. Taiwan High Speed Rail
  11. TGV
  12. Thalys
  13. Sapsan

Railway lines (4 articles)

  1. Trans-Australian Railway
  2. Chinese Eastern Railway
  3. Trans-Mongolian Railway
  4. Trans-Siberian Railway (Level 4)

Railway services (2 articles)

  1. Indian Pacific
  2. Orient Express


Categories