Workgroup:Categories/20091012 - First announcement
The following email was sent to the wikieducator google discussion group on 12 October 2009. 
There's another workgroup a-brewin' down on the wiki! This one is about categories; yes, dreadful fun, I know. Before I talk about the workgroup, I'd like to introduce you to the concept, and the rationale behind their use.
What are categories?
A category is just what it sounds like: a method of grouping pages according to their content. Categories also work with parent-child connections in the same way that subpages do. The category you put a page in will actually be a subcategory of another. A category system will have many levels within it. Where the category system gets even more useful than the subpage system is in the number of relationships that can be defined by it. While a subpage can only have one parent page, any page or category can be in as many categories as we like. This is where the mediawiki software becomes genius in its use of virtual reality; even though there exists only one document, at a single url, it can be found and related to other documents in any number of ways. This creates a powerful browseability that is trumped only by the searchability of the SemanticWiki extension, which involves a steep learning curve.
The category system is a built-in method of organising content far better than the subpage system method. It creates relationships between content that cannot be defined by subpages, making it easier for members to move from page to page and between related information. Want to know what other projects there are on astrophysics? The category system will tell you that. Want to be able to find all the resources from Otago Poly-Tech easily? Curious about what 10 year old children are learning elsewhere in the world? The category system allows for these. Using the category system is preferred over contents pages because it requires far less effort from members to keep current. To add a page to a category, one never has to leave the page, itself!
The other key factor for categorising pages is a concept called "search engine optimisation" (SEO). You may have heard of this if you are in any way involved with web publishing. I'm not going to explain SEO, but I will tell you the point of it is to increase readership organically (they come to us, we don't market directly to them). This is done by appealing to the formulas Google and other search engines use to determine who goes at the top of any search list. The thing is, if there aren't any links to your page, Google never sees it! Categories create a link-based map of the website, allowing Google's programs to see each page that has a category.
Sounds great, right? Well, WE's category structure is a bit out of shape at the moment. For example, about 30% of the categories used don't actually exist, yet; there are a handful of central/root/contents categories, none of which go deeper than a few levels; there are (as I write this) 12,200 uncategorised pages out of 68,992 total, or about 15%; and most of the existing categories aren't connected to any other category.
So, Alison Snieckus and I have seeded a workgroup to get WE's category system in tip-top shape, as well as working to educate WE members on categories and advise the style guidelines workgroup on guidelines that affect category usage. We're still organising the group, and there are some tasks to be done, and we could use your help with both! WE would really benefit from your opinions and ideas, so please stop by ( http://www.wikieducator.org/Workgroup:Categories ) and sign up. There are lots of informational links, and it isn't necessary you be an expert on wikis or the category system to take part, but you might find you know a lot more when we're all done. If you have any questions, please feel free to ask here, or on the workgroup talk pages. As with the style guide workgroup, membership isn't required to participate in discussions, it just helps us to know who wants to be involved so we can give them credit and to make sure everyone has something to do to help.
Looking forward to seeing you there!