What are Internet Directories and Search Engines?

Directories and search engines differ in at least two important ways: Who creates the list of Internet sources and how the list is arranged. Let's discuss each of these factors.

Type of Tool	Creator
Directories	Directories are compiled by staff members who gather sources by searching the Internet or through contributions from people using the directory.
Search Engines	Search engine databases are compiled electronically by computers that routinely visit sites on the Internet and copy their contents into the search engines' database.

As a general rule, directories tend to include fewer sites by being selective and filtering out many irrelevant sites. Search engines include more entries but many of those may not be what you need.

Type of Tool	Organization
Directories	Directories have an organization meant to be logical and helpful to its users. Many use a subject arrangement, breaking broad subject areas down into smaller, related sections.
>Search Engines	Search engines have no pre-existing arranged list. A list of Internet resources is retrieved when you do a search in the search engine's database.

Directories try to show the relationships among subjects. Search engines depend more on your choosing the "right" keywords.

Note that many Internet search sites offer both types of tools: directories and search engines. Some directories connect you to a search engine and some search engines offer a small directory of hand-picked resources organized in subject categories. There are variations within each type of resource. Multi-engine searching allows you to perform a search in several engines simultaneously. Specialized engines and directories often limit their contents to a particular subject area.

What do these differences mean for searching? Why would you choose a directory rather than a search engine, and vice versa? Let's examine these questions in the next section.