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Tuesday 12 June 2012

Using search services


Using search services

As you know, there is a vast ocean of information available on the World Wide Web. Search services help you to quickly locate information about a specific topic from multiple websites. A number of search tools have been developed and are available on different web sites. A search can be done by entering a keyword, a descriptive world or phrase or by browsing a topic list.
Search services can be categorized into two types, web directories and search engines. Web directories are databases of Internet sites that are organized by topics or subjects. Search engines are also huge databases of web sites, but typically offer no categories or differentiation between different types of material.
The search engines use a program called crawler or spider to check out websites, read and store specific types of information and add new sites to their existing database of sites. The database is updated periodically by the spider.
Search engines provide two different search approaches: Keyword search and Directory search. In a keyword search, you enter a keyword or phrase reflecting the information you want. The search engine compares your entry against its database and displays a list of “hits” in the form of hyperlinks to related web pages. For example, if you entered the keyword “travel” you get thousands of hits. These are ordered according to those sites most likely to contain the information requested and are usually in groups of 10.
You may find relevant information on the web using “Subject Directories”.  Subject directories are collections of Internet resources organized into subject categories. They are useful for looking for information on a specific subject or to gain familiarity with a topic. Advantages of subject directories are that they generally contain good quality sites and they save time since subject wise information is available.
Let us have a look at the Google subject directory. Enter the URL “http://directory.google.com” in the address bar and press “Enter”. You can see the Google directory on your screen showing links to various subjects. Clicking on a subject will show you more detailed lists from which you may make your selections.
Using the Search Box: One of the new features of Internet Explorer 7 is the “Search Box” located at the top right.  You can search the internet using most search engines from the search box instead of going to other search engine sites. If you want to find something on a page you are currently on, click on the down arrow to the right of the magnifying glass and select “Find on this Page”. Enter your search criteria and click “Next”.
Finding search services: There are numerous sites providing search services such as www.google.com, www.yahoo.com, www.ask.com, www.lycos.com, www.live.com and www.altavista.com. As all search engines use different techniques and resources, it advisable to use more than one search engine for conducting a search. You may add search providers to Internet Explorer 7. For this, click on the down arrow to the right of the magnifying glass and select “Find More Providers”. Then, click on the name of a provider in the displayed web page. Now click “Add Provider” in the window that comes up.
You may change the default search engine if you wish. For this, click on the down arrow to the right of the magnifying glass and select “Change Search Defaults”.  Click “Set Default” and then “OK” to make the search provider you just added as the default one.
Metasearch Engines: When you research a topic, you may need to visit different web sites in order to use different search engines. This would be time-consuming and duplicate responses would be inevitable. “Metasearch Engines” offer an alternative. They are programs that automatically submit your search request to several search engines simultaneously. The metasearch engine receives the results, eliminates duplicates, orders the hits and provides the edited list to you.
You can see a list of some metasearch engines available on the Web in the displayed table.
Specialized Search Engines: These search engines focus on subject-specific web sites. They save your time by narrowing your search. For a list of a few specialized search engines, have a look at the displayed table.
Content Evaluation: You must keep in mind that not all information available on the Web is accurate. In fact, anyone can publish content on the Web. Many sites such as Wikipedia.com, allow anyone to post new material, sometimes anonymously and without critical evaluation. To evaluate the accuracy of information found on the Web, you need to consider the following points.
Authority: Is the author an expert on the subject? Is the web site an individual’s personal one or an official one?
Accuracy: Has the information been critically reviewed for correctness? Does the web site provide a method of reporting inaccurate information?
Objectivity: Is the information reported biased or based on actual facts? Does the author gain personally by convincing the reader or changing his opinion?
Currency: Is the information up to date. Is the date when the site was updated specified?

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