Google.com is an example of a search engine. When you enter your search in a search engine, it searches within its own database of web pages for the keywords you enter, wherever they appear on a web page.
Search Engines
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Use search engines to find web pages containing information about:
specific terms or phrases
names of organizations or places or schools
news, travel and shopping services
image collections thousands of visual images representing any subject
a seemingly infinite variety of topics by people all over the world
Other search engines include: Excite, HotBot, and Alltheweb.