Since search engines retrieve vast amounts of information, software designers have created subject directories to organize this material into broad subject categories such as business, entertainment, and science.
Subject Directories are a good place to start searching the Internet when you do not know exactly what information you need. Many directories have their own keyword search engines which will speed you through the various levels of subtopics within a category.
Caution! Subject Directories contain only a small portion of available Internet sites. Use a search engine instead of a subject directory if your research needs are so specific that you will need to see many sites on your topic to get the information you need.
Yahoo: the largest subject directory on the Internet and one of the best for finding information about popular and contemporary topics.
About.com: broad-based subject directory that provides annotations about each site.