A web directory or link directory is a directory on the World Wide Web. It specializes in linking to other web sites and categorizing those links. Thus, in web directory, web sites are categorized by subject.
A web directory lists web sites by category and subcategory. The categorization is usually based on the whole web site rather than one page or a set of keywords, and sites are often limited to inclusion in only a few categories.
For example, Yahoo web directory includes categories for Arts & Humanities, Business & Economy, Computer & Internet, Recreation & Sports, Education & others. Each of these major categories contains many sub categories. For example, if we click on Recreation & Sports category, we can find Sports, Games, Travels, Outdoors and many other sub-categories.