What is the difference between google and a subject directory like yahoo

On a daily basis, we use search engines

and directories as tools to find information on the web. However, the

difference is how they get and organize their information.

Search engines use small programs like

bots or spiders that search thoroughly through the internet, follow links, and

sends back information to the search engine's index. Subject directories, on

the other hand, are human powered. Website owners submit their sites to

directories and human editors determine the value of the site and whether or

not it should be included in the directory.

Search engines use phrases and keywords

to locate information on the internet while subject directory allows users to

find information by using hierarchy.