From Extropia
Redirects are a handy little feature for a number of purposes. Why would you use them? Laziness is probably the best reason. But let us elaborate.
How to Use
A redirect prompt will take the place of any normal article. So, say you click a red link that needs a page associated with it, but the name doesn't match what it should be, such as a link to "The Div" where "The Diversionarium" is the article name. Click on "The Div" and you'll have a blank page. To get these links to point to "The Diversionarium", type the following:
#REDIRECT [[The Diversionarium]]
That's it. All it takes is for you to type a hash, YELL at the article to redirect, then type a link to the proper article just as you would in a normal page.
Of course, it's preferable to link to the proper article wherever possible to save on having swarms of these redirects. If a project, place or person has more than one name that users could be using in the search bar, then a redirect is very wise. However, if in cases like "Central Nexus" where people could simply be typing "Nexus", it would be preferable to keep the redirect within that article. To do this, simply type this in place of the regular link:
[[Central Nexus|Nexus]]
The vertical bar splits the actual link from the text that will replace it. In this case, "Nexus" replaces "Central Nexus" only in visual form.
Why would I use these?
As mentioned before, most redirects are to cover for alternative names, however many articles here will link to names personally, particularly when highlighting community projects which the Board has had no part in. By default these links will be written as "[[Joe Extropian]]", but each user already has their own page! We don't need two. The problem is that MediaWiki names these pages "[[User:Joe Extropian]]". If you wanted to be neat, you could use the steps outlined in the previous paragraph to redirect links on every article in which that name is referenced, but it would be easier to type names as links and forget about it. Simply create a link to your name, click the red link and type:
#REDIRECT [[User:Joe Extropian]]