Internet Search Engines: A Guide to Searching
This page introduces major Internet Search Engines and provides general information on how to perform a basic internet search.
What types of Search Engines are there?
There are three types of Internet Search Engines:
- Directories or Tree-structured Search Engines
- General Search Engines
- Metacrawlers or Metasearch Engines
When would I use one type of Search Engine over another?
The first and most important step in retrieving quality results from the internet is deciding which search engine offers you the greatest chance for a successful search. With each search engine, you'll find differences in the number of websites indexed, how these sites are indexed, and differences in the way the results are ranked or listed. Being aware of such differences can help you narrow your search and quickly find the information you are looking for.
How can I get the best results when I'm searching?
As mentioned above, getting the best, quickest, and most accurate results begins with choosing the most appropriate search engine. Once you have decided which is the best search engine, you will need to know some basic search techniques in order to achieve quality results. The most typical problem associated with the internet is that a search returns too many results to decide between. If you can accurately limit your results, you automatically reduce the number of websites you will have to evaluate.
Directories
Internet Directories generally search only those sites they have personally selected or reviewed. Because each site is inspected by humans, not computers, these search engines will not usually return large numbers of irrelevant websites. Generally, only a few access point to a website are listed at a time, which helps guide the searcher to the most important page from a large website and reduces the number of extra hits to the website's subpages.
Internet Directories generally arrange their indexed websites into categories that can be easily browsed. They also allow you to search their index of terms, or the terms they have selected to represent the website. This means you are not searching the full text of a website. It's like the difference between looking for a subject in a book's index or being able to scan the whole text for your word.
Yahoo! is the largest, oldest, and most popular directory, but some of the major internet directories are:
Search Engines
While still drastically incomplete in their coverage of the internet, Search Engines provide access to the greatest portion of available websites. (A recent study determined that the most comprehensive search engine allow access to approximately only one-sixth of the Web's estimated 800 million pages and that the combined use of eleven search engines provided access to only 42 percent of the Web's pages.) One advantage of search engines over directories is that they usually allow "full-text" searching of webpages.
Search engines work by using "spiders" or "crawlers" to continually visit web pages and follow each link, recording information as they go. Everything they encounter is woven into a giant index which can then be searched by the engine's software. The software explores the index to find the most relevant matches for a search. Because both spiders and software vary, the same search will yield different results from one engine to anothe. Because search engines do provide near "full-text" access to what webpages they do index, they are extremely powerful and are the best place to go when specific information is needed.
Some of the more popular general search engines include:
Many general search engines provide classified, tree-structure browsing intended to help you identify websites associated with your topic. These indices are often cumbersome and difficult to navigate and also typically index only the most popular sites, not the best sites available. Use caution when browsing these areas and perhaps ask yourself whether one of the other search engines or directories may be of more use for your search.
Metacrawlers or Metasearch Engines
(uses more than one search engine at a time)
Metacrawlers, also called metasearch engines, do not send out their own crawlers to build an index. Instead, a metacrawler enables the search to be run in several search engines at the same time. Results are gathered and grouped on the metacrawler page. Each different metacrawler features a unique combination of search engines and its own method of reporting results, so similar searches will produce different outcomes across metacrawlers.
Metacrawlers work especially well when no searching has been done in a subject area and the goal is to get an overview of what is available where. A metasearch can help determine the best direction for further research. Note: No specialized functions unique to individual search engines work within metasearches, which can be considered a distinct disadvantage over submitting to individual search engines.
Some of the more popular metasearch engines include:
International Search Engines
Some standard search engines have created versions for foreign users. For a look into some search engines that may have a distinctly non-American scope, try some of the sites below. Keep in mind, as with all search engines, the various possibilities for searching, the scope of the search engine, and the type of results you will likely find.
Directories
Internet Directories generally search only those sites they have personally selected or reviewed. Because each site is inspected by humans, not computers, these search engines will not usually return large numbers of irrelevant websites. Generally, only a few access point to a website are listed at a time, which helps guide the searcher to the most important page from a large website and reduces the number of extra hits to the website's subpages.
Internet Directories generally arrange their indexed websites into categories that can be easily browsed. They also allow you to search their index of terms, or the terms they have selected to represent the website. This means you are not searching the full text of a website. It's like the difference between looking for a subject in a book's index or being able to scan the whole text for your word.
Yahoo! is the largest, oldest, and most popular directory, but some of the major internet directories are:
Search Engines
While still drastically incomplete in their coverage of the internet, Search Engines provide access to the greatest portion of available websites. (A recent study determined that the most comprehensive search engine allow access to approximately only one-sixth of the Web's estimated 800 million pages and that the combined use of eleven search engines provided access to only 42 percent of the Web's pages.) One advantage of search engines over directories is that they usually allow "full-text" searching of webpages.
Search engines work by using "spiders" or "crawlers" to continually visit web pages and follow each link, recording information as they go. Everything they encounter is woven into a giant index which can then be searched by the engine's software. The software explores the index to find the most relevant matches for a search. Because both spiders and software vary, the same search will yield different results from one engine to anothe. Because search engines do provide near "full-text" access to what webpages they do index, they are extremely powerful and are the best place to go when specific information is needed.
Some of the more popular general search engines include:
Many general search engines provide classified, tree-structure browsing intended to help you identify websites associated with your topic. These indices are often cumbersome and difficult to navigate and also typically index only the most popular sites, not the best sites available. Use caution when browsing these areas and perhaps ask yourself whether one of the other search engines or directories may be of more use for your search.
Metacrawlers or Metasearch Engines
(uses more than one search engine at a time)
Metacrawlers, also called metasearch engines, do not send out their own crawlers to build an index. Instead, a metacrawler enables the search to be run in several search engines at the same time. Results are gathered and grouped on the metacrawler page. Each different metacrawler features a unique combination of search engines and its own method of reporting results, so similar searches will produce different outcomes across metacrawlers.
Metacrawlers work especially well when no searching has been done in a subject area and the goal is to get an overview of what is available where. A metasearch can help determine the best direction for further research. Note: No specialized functions unique to individual search engines work within metasearches, which can be considered a distinct disadvantage over submitting to individual search engines.
Some of the more popular metasearch engines include:
International Search Engines
Some standard search engines have created versions for foreign users. For a look into some search engines that may have a distinctly non-American scope, try some of the sites below. Keep in mind, as with all search engines, the various possibilities for searching, the scope of the search engine, and the type of results you will likely find.
Choosing the Best Internet Search Tool
Everybody has his or her own favorite internet search resource. Some people only use Altavista, others always begin their internet searches with Yahoo! Deciding what resource is best for your needs is necessary for any type of research you conduct, and the internet is no different. Considering some of the questions below may help you decide where to start.
- Before you even click on that internet browser, ask yourself (or a reference librarian) whether the internet is really the best place to find the information you are looking for? Remember that the internet is a modern resource, that many of the databases available through the internet only index journals back into the early 1980s, and that the quality of information represented is sporadic. You must consider whether print resources exist which would provide more accurate information, more comprehensive information, or more reliable information.
- Once you have decided the internet may hold useful information about your topic, you should evaluate your topic to determine which type of search resource would be most effective or most likely to bring you quick and accurate results.
- Directories are often helpful when you are browsing a topic and are particularly helpful when locating government or business webpages.
- Search Engines are extremely helpful when you are searching for a unique phrase. They usually index a greater number of webpages than directories, so while you will be more likely to find obscure information using a search engine, you may have to sort through more results to find it.
- Metasearch Engines are useful when you need to find information from a number of engines simultaneously. While this has several advantages, you should be aware that most metasearch engines only return the first 10-20 results from each search engine. If your search is not specific enough, that may result in a loss of important, but poorly indexed, information from the individual search engines.
Everybody has his or her own favorite internet search resource. Some people only use Altavista, others always begin their internet searches with Yahoo! Deciding what resource is best for your needs is necessary for any type of research you conduct, and the internet is no different. Considering some of the questions below may help you decide where to start.
- Before you even click on that internet browser, ask yourself (or a reference librarian) whether the internet is really the best place to find the information you are looking for? Remember that the internet is a modern resource, that many of the databases available through the internet only index journals back into the early 1980s, and that the quality of information represented is sporadic. You must consider whether print resources exist which would provide more accurate information, more comprehensive information, or more reliable information.
- Once you have decided the internet may hold useful information about your topic, you should evaluate your topic to determine which type of search resource would be most effective or most likely to bring you quick and accurate results.
- Directories are often helpful when you are browsing a topic and are particularly helpful when locating government or business webpages.
- Search Engines are extremely helpful when you are searching for a unique phrase. They usually index a greater number of webpages than directories, so while you will be more likely to find obscure information using a search engine, you may have to sort through more results to find it.
- Metasearch Engines are useful when you need to find information from a number of engines simultaneously. While this has several advantages, you should be aware that most metasearch engines only return the first 10-20 results from each search engine. If your search is not specific enough, that may result in a loss of important, but poorly indexed, information from the individual search engines.
Getting Better Results While Searching
Each search engine has its own unique features which may help you focus your search for better, more accurate results. To learn more about these features, you should look for the search engine's Help button, usually included near the top of the webpage.
1.) Use Exact phrases: If you know an exact phrase, put the phrase in quotes, for example: "golden gate bridge". The search results will return only websites that contain these exact words, with their exact spelling, and in the exact order you specify. If a returned page does not contain this phrase, the reason may be that the page at that particular URL was updated, but the page hasn't been indexed again by the search engine.
2.) Specify a particular Language: Some search engines allow you to specify a particular language (typically through a pull-down menu near the search box), so you can find all the documents on the Web about a given topic, written only in the language you specify.
3.) Use lowercase text in your searches: In many cases, when you use lowercase text, the search engine finds both uppercase and lowercase results. When you use uppercase text, some search engines only find uppercase results.
Example: When you search for california, you'll find California, california, and CALIFORNIA in your result pages. However, when you search for California, you'll only see California in the result pages.
4.) Include or exclude words:
- To make sure that a word is always included in your search, place a plus sign (+) immediately before the keyword (no spaces) in the search box.
- To make sure that a word is always excluded from your search, place a minus sign (-) immediately before the keyword (no spaces) in the search box.
Example: To find recipes for chocolate cookies without chips, try searching:
recipe cookie +chocolate -chips.
5.) Use wildcards: By typing an asterisk (*) at the end of a keyword, you can search for multiple forms of the word.
Example: Try big*, to find big, bigger, biggest, and bigwig.
Each search engine has its own unique features which may help you focus your search for better, more accurate results. To learn more about these features, you should look for the search engine's Help button, usually included near the top of the webpage.
1.) Use Exact phrases: If you know an exact phrase, put the phrase in quotes, for example: "golden gate bridge". The search results will return only websites that contain these exact words, with their exact spelling, and in the exact order you specify. If a returned page does not contain this phrase, the reason may be that the page at that particular URL was updated, but the page hasn't been indexed again by the search engine.
2.) Specify a particular Language: Some search engines allow you to specify a particular language (typically through a pull-down menu near the search box), so you can find all the documents on the Web about a given topic, written only in the language you specify.
3.) Use lowercase text in your searches: In many cases, when you use lowercase text, the search engine finds both uppercase and lowercase results. When you use uppercase text, some search engines only find uppercase results.
Example: When you search for california, you'll find California, california, and CALIFORNIA in your result pages. However, when you search for California, you'll only see California in the result pages.
4.) Include or exclude words:
- To make sure that a word is always included in your search, place a plus sign (+) immediately before the keyword (no spaces) in the search box.
- To make sure that a word is always excluded from your search, place a minus sign (-) immediately before the keyword (no spaces) in the search box.
Example: To find recipes for chocolate cookies without chips, try searching:
recipe cookie +chocolate -chips.
5.) Use wildcards: By typing an asterisk (*) at the end of a keyword, you can search for multiple forms of the word.
Example: Try big*, to find big, bigger, biggest, and bigwig.
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