Search Engines

What is a Search Engine?

Software programs that search the Internet for a topic, catalogs the results, and displays the sites found.

Also called Spiders or Web crawlers Save time in researching by displaying

descriptions to be read before visiting sites found.

Types of Engines

Subject-and-Keyword – build their own catalogs by gathering and organizing it from other sites prior to being asked for a specific search string.

Types of Engines

Multi-threaded engines – are slower search engines because they don’t maintain their own catalog. They search specific strings only when asked.

Catalogs

Hierarchical – Goes faster because a person is able to narrow their search by categories prior to asking a search engine to find a specific search string.

Subject – looks for the word but may bring up other topics

Text String

Words or phrases used to narrow a search area

Searches

Simple Search – uses only one or two keywords (broadest kind)

Complex Search – uses Boolean operators (AND, OR, NOT, etc.) and grouping operators (double quotes, parentheses) (contains several words and also operators to modify the text string)

Error Messages

Site may be busy or temporarily down Either server or site may no longer exist Server unavailable at this time Server not found Unable to find a file

What to Do

Check for typographical mistakes Check for proper capitalization of proper nouns Check the spelling of keywords Try spelling variations of keywords Try a different search site