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. A web directory is not a search engine, and does not display lists of web pages based on keywords, instead it 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 one or two categories. Web directories often allow site owners to directly submit their site for inclusion, and have editors review submissions for fitness.

Some directories are very general in scope and list websites across a wide range of categories, regions and languages. But there are also a large number of niche directories, which focus on restricted regions, single languages, or specialist sectors. One type of niche directory with a large number of sites in existence, is the shopping directory for example. Shopping directories specialize in the listing of retail e-commerce sites.

A human-edited directory is created and maintained by editors who add links based on the policies particular to that directory.

Human-edited directories are often targeted by SEOs on the basis that links from reputable sources will improve rankings in the major search engines. Some directories may prevent search engines from rating a displayed link by using redirects, nofollow attributes, or other techniques.

Many human-edited directories, including the Open Directory Project and the World Wide Web Virtual Library, are edited by volunteers, who are often experts in particular categories. These directories are sometimes criticized due to long delays in approving submissions, or for rigid organizational structures and disputes among volunteer editors..