Sometimes, it might be useful to look up a subject in the same way you would do so in a book—in the index. Wikipedia has an index. To use it..

1. click on the Special pages line of the Tools menu
2. from the Lists of pages section, click on the All pages with prefix link
3. at Display pages with prefix: type the beginning of the article's name into the box and press Go.

You will see a list of all pages that begin with what you typed.

You can reduce the number of articles displayed in this list by typing more of the name and pressing Go again. You can also find Wikipedia users in a similar way by changing the entry in the drop-down box labelled Namespace, from (Article) to User.