In Wikipedia, the color of links show the status of the corresponding page. The colors are the following:
A blue link, like this one, is a link to an article that exists within the current Wikipedia project site.
A red link, like this one, is a link to an article that does not yet exist within the current Wikipedia project site.
A light blue link, like this one, is an InterWikimedia link. The bright blue color is used regardless of whether or not the article actually exists at the Wikimedia project site. For example, this article of George Washington exists on this English Wikipedia project, while this article of the same subject links to the Japanese Wikipedia project. External links will display in light blue as well.
The color values are as follows. The boxes may appear darker than text of the same color would appear.