• Search engines vary in format, extras, and often (but not always) the quality of results. Some overlap does exist.

 
• Each search engine has its quirks, but on the whole are operated by users in the same way.

 
• Remember that even the best search engine covers no more than 40% of the entire Internet.

 
• Search engine ranking programs are idiosyncratic at best. Don't rely only on the first 10 results.

 
• For any serious research project at least three search engines and metasearch engines should be used.

 
• Evaluate a search engine based on its results and what the engine thinks it does and is. Use--but do not rely solely on--search engine evaluation sites, such as Search Engine Watch, at http://www.searchenginewatch.com/.

Google, found at http://www.google.com/, is one of the Internet's most popular search engines. It has the cachet of being both popular and critically respected.

• Its claim to search the most sites of any search engine must be viewed dubiously, but the number of sites it actually searches is still very high.

 
• Quality of results is usually high, although the sites are sorted on popularity rather than a ranking formula.

 
• Excellent layout scheme leads to high utility. Google is a search engine and only a search engine.

 
• Allows for both Boolean and natural language searching.

 
• Google caches viewed sites, which is enormously valuable given the transient nature of many sites.

 
• Makes use of the Netscape Open Directory Project, but is a search engine first and a directory second.

 
• Has very good Advanced Search and Preferences options.

 
• Should have Deja's archive of Usenet posts up and running in a a couple of months.

 

Northern Light, found at http://www.northernlight.com/, is not as well known to the general public as Google, but has a well-deserved reputation among professional researchers.

• The number of sites they search seems to be less than Google's but is usually of a higher quality, leading to roughly equal results, albeit fewer of them.

 
• Drawing from a smaller pool of sites leads to some curious omissions, however. Northern Light should be used for quality searches, rather than a brute force search.

 
• Their "Special Collection" option allows you to buy articles from journals, newspapers, books, and other sources; if you do not have access to databases this is a good substitute.

 
• Boolean searching.

 
• Northern Light automatically reorganizes your results into theme-based Custom Search Folders.

 
• Has a good Power Search option.

 

Altavista, found at http://www.altavista.com/, is one of the better standard search engines. Until recently it was attempting to be an all-things-to-all-people portal, but they have returned to being primarily a search engine.

• Large number of sites searched, and of generally good quality.

 
• Boolean searching.

 
• Results vary in utility; a lack of specificity on the searcher's part can lead to irrelevant results.

 
• An uneasy attempt to combine the features of a directory and of a search engine.

 
• Allows you to specify what language you want to search in.

 

All The Web, found at http://www.alltheweb.com/, came in second in a recent survey of search engine size.

• Large number of sites searched, and of generally good quality.

 
• Quality of search results generally good but there are numerous omissions.

 
• Boolean searching.

 
• The Advanced Search feature is good.