searchengines

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Internet Search Engines

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What is a Search Engine?

Search engine is a general term that refers to internet databases or indices of web sites. There are three basic kinds:

True search engines. These create lists automatically by “crawling” the internet in search of the word(s) you specify. HotBot and AltaVista are examples.
Directories. These create lists by the input that reviewers (people) provide. A reviewer checks out a web site, indexes it under keywords, and gives it a rating. Yahoo is an example.
Metacrawlers. These create lists automatically by having several search engines and/or directories retrieve results that match your query. Metacrawler and NetFirst are examples.

Wonderful information about how search engines work, where to find them, and how to use them can be found at Search Engine Watch.

How do I use a Search Engine?

Most search engines have a “search tips” section that will help you refine your search. The simple math functions (+, -) and the more complex Boolean operators (and, not, or) may help you clarify your search.

Math Functions
Use these simple terms to help you refine your internet searches. These terms work for almost all engines and directories.

Plus Symbol
+
Use the plus symbol to add ideas together. The results will give you everything with all the terms in your search. For example, a query for +salmon +dams would give you all the results with both terms. (Like the Boolean operator "and.")

Minus Symbol
-
Use the minus symbol to subtract an idea so that the results will give you everything on one subject without the other. For example, a querie for salmon - dams would give you all of the results about salmon without the mention of the word dam. (Like the Boolean operator "not.")

Boolean Operators
Use these terms to help refine your internet searches farther than math functions will allow.

AND Sites where two ideas overlap. For example, a query for "salmon AND dams" would give you all the results that have both of the terms "salmon" and "dams." (Like the math function +.)

OR Sites where either or both of the two ideas are found. For example, a query for "salmon OR dams" would give you all the results where "salmon" or "dams" or "salmon and dams" are found.

NOT Sites where only one idea is found. For example, a query for "salmon NOT dams" would give you all the results where "salmon" is found but not "dams" or "salmon and dams." (Like the math function -.)

Search Engines

All in One Searches & Metacrawlers
These search engines querie lots of other search engines then combine the results for you. All in one search engines are the easiest to use and allow you to choose the search engines to search. Metacrawlers send you to specific search engines for the results.

All in One
All-in-one Search Page

Metacrawlers

Basic Search Engines & Directories
These traditional search engines and directories will help you find information online about the terms you enter. Most of them are commercially based.

Yahoo!

Alta Vista

Infoseek

Hot Bot's SuperSearch

Northern Light Search

Plus Symbol +	Use the plus symbol to add ideas together. The results will give you everything with all the terms in your search. For example, a query for +salmon +dams would give you all the results with both terms. (Like the Boolean operator "and.")
Minus Symbol -	Use the minus symbol to subtract an idea so that the results will give you everything on one subject without the other. For example, a querie for salmon - dams would give you all of the results about salmon without the mention of the word dam. (Like the Boolean operator "not.")

AND	Sites where two ideas overlap. For example, a query for "salmon AND dams" would give you all the results that have both of the terms "salmon" and "dams." (Like the math function +.)
OR	Sites where either or both of the two ideas are found. For example, a query for "salmon OR dams" would give you all the results where "salmon" or "dams" or "salmon and dams" are found.
NOT	Sites where only one idea is found. For example, a query for "salmon NOT dams" would give you all the results where "salmon" is found but not "dams" or "salmon and dams." (Like the math function -.)