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PART I: First, you should know that there is more than one type of "Search Engine". The most inclusive of these are called "Portals" or Directories and are the ones you more commonly hear of (Yahoo!, Excite, Lycos). The reason for naming them "Portals" is they are more than just a search site, but a site that provides you with Internet services: email, chat rooms, shopping, guides, etc. They usually have actual people that will sort through the listing of web sites that come in and decide what category the site should go under. They will have Category listings to guide you to sub-categories until you break it down to a specific enough topic to return web site addresses. Portals also have some of the disadvantages in that they control the content that you are able to find. They are a good aid for new users to get acquainted with what's out there and what can be done, but at the same time, they only give you a small part of the Internet. Portal sites often point you to sites that are affiliated with their site, rather than to the most relevant or informative site on your searched topic. On the other hand, sometimes using an directory is the best way to find what you want, particularly if you are certain that the site exists and you know a bit about where it resides. Some search engines are meta search engines. These engines do not maintain their own databases but search those of other engines. Metacrawler, for instance, searches the databases of each of the following engines: Lycos, WebCrawler, Excite, Alta Vista, and Yahoo. As described by its FAQ file, "MetaCrawler queries the other search engines, organizes the results into a uniform format, ranks them by relevance, and returns them to the user. Of course, this means that MetaCrawler is slightly slower than other engines, but is more likely to obtain accurate results for your query." Dogpile is a relatively new meta search engine which is also a popular tool. It searches Yahoo!, Lycos' A2Z, Excite Guide, GoTo.com, PlanetSearch, Thunderstone, What U Seek, Magellan, Lycos, WebCrawler, InfoSeek, Excite & AltaVista search engines as well as USENET NEWS, FTP and NEWSWIRE sites. The last type of search engine is called a micro search engine because it specializes in a category. There are micro engines for all different kinds of occupations and hobbies. I will try to list a few in our search engine list, but there are so many of them that I couldn’t possible list them all. You can use other engines and portals to locate the micro engines. Search engines store information about web documents under several categories or fields in a large database. It has fields for author, title, date and subject and the more comprehensive a database, the more fields it will contain. For instance, additional fields may be keywords contained in the document, the URL, an abstract of the document, and more. Both AltaVista and OpenText have the entire text of a web document stored in a searchable field so if a keyword is anywhere in a document, that document will be retrieved by the engine. PART II: How To Search After you decide which type of engine will suit your needs best and pick the one that you want to use, you may find these tips helpful. Start by trying to think of words that best describe what you are looking for. The more words that you can include in your searches, you closer you will probably come to finding what you want. If you just type the words in without any other characters, the search engines will look for each individual, without checking for any relation to any of the other words in the search criteria. For example, if I type in ‘basketball NC chapel hill’ on the search line, the engine will return anything it finds about basketball, North Carolina, chapel and hill. So you can see I am not going to get what I was looking for. To group sets of words together, you can enclose them in quotes (Ex. "Chapel Hill"). Now the search engine will look for the whole string Chapel Hill and not chapel and hill separately. Next, you can separate groups of words by using "AND" and "OR". This has the effect of limiting or expanding the search results. These are referred to as Boolean operators. "AND" limits a search and "OR" expands it. If you ask for all documents which contain the word "basketball" AND "NC", you will get more specific pages than asking each thing separately. Conversely, if you ask for all the documents which contain the word "basketball" OR the word "NC", you get all the pages that contain "basketball" and all the pages that contain "NC", regardless if the other word is present. Some search engines allow the use of wild cards. A wild card is a character which can be appended to the root of a word so that you can search for all possible endings. For instance, you may be looking for information on the harmful effects of smoking. Documents which contain the following words may all be useful to your search: smoke, smoking, smokers, smoked, smokes. If a search engine allows wild cards, you can enter "smok*". The asterisk is the wild card and documents which contain words that start with "smok" will be returned. Try it now. Go to each search engine and enter a word that has more than one possible ending. Then search again using the root of the word plus a wild card. Compare the results. PART III: Finally, I will leave you with this:
"The coverages of the search engines vary by an order of magnitude. An estimated lower boundary on the size
of the indexable Web is 320 million pages. The engines index only a fraction of the total number of documents on the Web; the
coverage of any one engine is significantly limited." In other words, no search engine has a list of ALL internet sites. Each engine will probably return some different entries, so try different engines when you are searching. The last report I heard said that Northern Light engine has the greatest number of pages listed, but that is still only 16% of all of the over 800 million web pages on the internet today. Happy searching and surfing!
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