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Searching the World Wide Web
Summary: This section covers finding sources for your writing in the World Wide Web. It includes information about search engines, Boolean operators, web directories, and the invisible web. It also includes an extensive, annotated links section.
Searching the World Wide Web: Overview
Searching the World Wide Web can be both beneficial and frustrating. You may find vast amounts of information, or you may not find the kinds of information you're looking for. Searching online will provide you with a wealth of information, but not all of it will be useful or of the highest quality.
The World Wide Web is a superb resource, but it doesn't contain all the information that you can find at a library or through library online resources. Don't expect to limit your search to what is on the Internet, and don't expect search engines to find everything that is on the Web.
Studies of search engine usage show that search engines are increasing exponentially in their indexing of new websites and information. Indexing is the web term for finding and including new web pages and other media in search results. For example, in 1994, Google indexed approximately 20 million pages. As of 2004, that number is up to 8 billion! However, search engines still only index a fraction of what is available on the Internet and not all of it is up to date. Search engines may only "crawl" sites (or revisit them for purposes of indexing) every month or so; information that has been updated since that time will be invisible to the search engines. After you try several search engines, you will see that you get different results from different sites. Also, remember that some information appears and then disappears from Web sites. Finally, search engines don't always search the entire page; if a page is larger than 100 to 500 k, many search engines will only index the first 100 to 500k of the page. So there could be valuable information that is being overlooked by a search engine even in pages that are indexed.
Not all of the information located on the Internet is able to be found via search engines. Researchers Chris Sherman and Gary Price call this information the "invisible web" (another name that is frequently used is the "deep web"). Invisible web information includes certain file formats, information contained in databases, and other omitted pages from search engines.
So, using search engines is not the only way to find material on the web, but they are one tool you can use. Knowing a few search strategies and hints, as you use these engines, can make the search more profitable. This guide provides information on the different ways of locating material on the web including using search engines, searching the invisible web, and using web directories.