Categories are a feature that let you easily organize pages in SeattleWiki. Each page can belong to one or many categories; users can then browse through categories to find pages more easily.
For example, take a look at a list of all categories, or at some sample categories: general resources, Movie theaters, or restaurants.
To add a category to a page, simply add a line to it, at the end of the page, like:
[[Category:My category]]
For example: [[Category:General resources]].
If you want to a link to a category page from a different page, you need to add a colon (":") in the link, so that the page itself doesn't get put into that category instead. For example, to link to the general resources category, you would use [[:Category:General resources|]]. The "|" symbol at the end is used to hide the "Category:" part of the page name.