Web Search Engines

AltaVista

Run by Digital Equipment
Simple search does text search
Most comprehensive
Advanced search uses Boolean Operators
- Advanced search can limit search by date
- Advanced search can prioritize results
Does not rank sites, just looks for text

Searches by text
Offers "Query by Example", which allows you to search for similar pages, without requiring you to redefine search
Quite basic and simple to use
Opening screen asks you to search by either "keyword" or "concept", but both give you similar, if not the exact same result
Does not allow you to change original query from the results page
- Instead, you must click on "Refine Search"
Ranks sites from 0-100%, but it is often an innaccurate measurement

Instead of using * as the symbol for wildcard, the $ symbol is used
Text search, as well as index search
Able to find more pages than Excite or Infoseek, but still falls behind AltaVista
Highlights occurences of keywords in the results page
"Stems" words, meaning a search for "paper" will also search for "papers"
Allows for exclusion of certain pages that have a specified keyword
Does not allow user to specify a required keyword to be present
You can't match complete phrases
Incapable of Boolean searches

AOL's search engine
Very simple interface (good for beginners)
Boolean Operators can be used
Quotation marks can be used to denote a sequence of words
Does not have a lot of sites under its search functions, making it less effective
Usually gives you few matches

It's actually a searchable index
Relies on real people to visit sites and summarize them and categorize them
Simple enough for beginners
When you search, you can search for a word in the category title, or in its site summary
Very easy to locate similar sites
Results page highlights the best sites, and puts them at the top of the list
By cataloging the web, the results aren't as broad
Doesn't allow for text search in the contents of the page, so keywords must be in the summary or category name
It does have "Open-text" function which performs text searches, but isn't very good

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