The easiest way to learn when to link is to look at Wikipedia articles for examples. If you're trying to decide whether to make a link or not, ask yourself "If I were reading this article, would the link be useful to me?"
When you want to make a link to another Wikipedia page (called a wiki link) you have to put it in double square brackets, like this:
If you want the display text of the link to have a different title, you can do so by adding the pipe "|" divider (SHIFT + BACKSLASH on English-layout and other keyboards) followed by the alternative name. For example:
[[Target page|display text]]
Please check your links to ensure they point to the correct article. For example, Apple points to the article about the fruit, while Apple Computer is the title of the article about the computer manufacturer. There are also "disambiguation" pages - these are not articles, but pages which contain links to articles with similar titles. Some, such as Apple (disambiguation) are obvious, while others such as Georgia use generic titles. These differing titles make piped links especially useful, as a link to Georgia (country) is far less readable than a piped link called Georgia.
Linking dates may not seem useful; however, please link dates since it enables the use of a user preference in how dates are displayed. An unlinked date, like July 13, 2004, will always be displayed in that manner. If you link the date:
[[July 13]], []
Wikipedia will display it in one of the following ways:
July 13, 2004
13 July 2004
2004 July 13
-according to the preference set by the individual user. (This feature is only available to logged-in users and only works if the date is linked.)
It is very important to put in the correct categories so that other people can easily find your work. The best way to find which categories to put in is to look at pages on similar subjects, and check which categories they use. For example if you write an article about a type of tree, you may look at an article on another type of tree to see which categories could be appropriate.