Directories & Engines
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Directories & Engines |
| Subject Directories |
Usually have smaller databases than search engines
Classify web documents or locations into a subject classification scheme
Are usually compiled by hand or in some type of logical order
Usually provide limited search results of available pages on the Web
Begin with general topics and allow the user to narrow to a specific category
Will not be as comprehensive as the information located from a search engine
Will contain more specific information dealing with a particular subject matter.
| Search Engines |
Are programs that run on a particular web site
Index words or terms in web documents
Create their listings dynamically
Search large portions of the Internet based on information that their "spiders or robots" retrieve
Spiders or robots are automated search programs that go through the Web and search web pages for keywords
The information that spiders or robots return is used to match web pages to keywords and
key phrases requested by users and provide more comprehensive results of available sites on the Web
Information is submitted by users who want their sites included in the search database
Provide more complete search results of available pages on the web
Provide a larger amount of possibilities
| Multi/Mega Engines |
Doesn't create its own database of information
Searches the databases of other engines
Allows the user to search several search engines simultaneously
Search databases of other search engines
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