Site Category.
Most websites fit into a category of some sort: business sites can usually be categorized by the products and/or services offered, sites with technical documentation could be classified by the subject being documented and so on.
Categorize your site
Have a look at a popular search engine or web directory (such as LookSmart, Infoseek, Google or Yahoo) and look at the categories (and sub-categories) they use to classify sites. Will your site fit into one of them? Two of them? More?
Do not over-classify your site
Be careful not to make your site too general, fitting it into numerous main categories. This may be OK for a personal site, but if you are designing a website for a company, decide what is really necessary and what can be left out. Concentrate on the core business and mention other elements in just a few paragraphs or on one page (perhaps entitled Other services we provide).
If you have had a good look at the classifications available on the search engines, you will find that your site may fit into many different categories and sub-categories. Stick to the most relevant ones.
Further reading
For a business site it is important to think about how people will locate your site. Having categorized your site will make it easier when you set the site up for listing with Search Engines.
Bear in mind that submitting your site to Search Engines does not guarantee they will be listed, but that's another subject altogether, which I hope to cover at a later date.
Here are some more Search Engines and Directories:
Of course, there are many more search engines and catalogues, including local directories. For instance, for Perth, Western Australia, the folowing directories exist (perhaps even more):
