Searching the Web

Eastern Mediterranean University School of Computing and Technology Department of Information Technology ITEC229 Client-Side Internet and Web Programming Searching the Web CHAPTER 2 Prepared by: R. Kansoy

Contents 2.1 Searching the Web 2.2 Search Engines 2.3 Searching Techniques http://sct.emu.edu.tr/it/itec229

2.1 Searching the Web • If you don't know which site to go to for the information you're looking for you are goingto have to search the Web. • The Web is a worldwide resource ofinformation. • A primary reason that people usethe Web is to search for specific information,including text, pictures, music, and video. • There are many free services you can use to find information on the Web; • Search Engines, Search Directories, and Meta Search Engine • Some Web sites offer the functionality ofboth a search engine and a subject directory. http://sct.emu.edu.tr/it/itec229

2.1 Searching the Web • Search engines constantly visit Web sites in order to catalog Web pages. • Directories are created by humans who assign submitted sites to an appropriatecategory or categories, such as sports or shopping,and related subcategories. • Meta search engines are search tools that search several search engines atonce. • Examples: Search Directory – Yahoo, Search Engine – AltaVista, Meta SearchEngine - Mamma. • You can browse through categories, such as arts or sports, to find information thatinterests you or you can search for a specific word or topic. http://sct.emu.edu.tr/it/itec229

2.1 Searching the Web Limitations of Internet Research • Information Available • Amount of Time • Quality of Information • There are limitations of using the Internet as a research tool. People oftenhave the misconception that the Internet contains every bit ofknowledge...every piece of information ever written, and that all they haveto do is type in their subject and they'll be able to pull up exactly what theywere looking for. • The Internet doesn't contain every piece of information ever written andprobably never will. There have been millions if not billions of books andarticles published over time and only a fraction of the informationcontained within them is on the Internet. The information doesn't magicallyappear, someone has to put it on the Internet. http://sct.emu.edu.tr/it/itec229

2.1 Searching the Web • In addition, searching for information on the Internet often takes a greatdeal of time if you don't know of a site that contains the information. • Depending on your subject and which search engine you use, you maypull up several thousand web pages. And you may look through all of thepages, which could take hours, and even then you may not find whatyou’re looking for. On the other hand, you can sometimes find a great sitewith the information you need in only a few minutes. • Also keep in mind that since no one controls the Internet, anyone can putinformation on it. Some of that information may be useful and some of itbe garbage and useless as a source for research. http://sct.emu.edu.tr/it/itec229

2.2 Search Engines • A search engine isa program that finds Web sites, Web pages, documments, images, videos, news, maps, and other informationrelated to a specific topic. • A search engine is helpfulin locating information for which you do notknow an exact Web address or are not seekinga particular Web site. • Are like the index in the back of a book • Search engines require that you enter a wordor phrase, called search text or search query,that describes the item you wantto find. • Each word in the searchtext is known as a keyword. http://sct.emu.edu.tr/it/itec229

2.2 Search Engines • Thousands of searchengines are available. • Some search throughWeb pages for all types of information. • Othersearch engines can restrict their searches toa specific type of information, such as thefollowing items: http://sct.emu.edu.tr/it/itec229

2.2 Search Engines • Pros • Large chunk of publicly available web • Best way to search for specific info on the web • Cons • Too much info!! • Too many irrelevant hits http://sct.emu.edu.tr/it/itec229

2.2 Search Engines • How do they work? • Crawl the web with “spider” or “bots” • Travels from link to link • Collects information on publicly available pages • Creates an index of all these sites • Matches the search terms you enter to the index • Presents the search with the results list, or “hits” http://sct.emu.edu.tr/it/itec229

2.3 Searching Techniques How to Search? • What do you need to know about your topic? • Make a list of all the terms connected with your topic. • Include names, organizations, and phrases. • Make a list of the words that are critical to your search. • Note terms that you don’t want to see appear. • Discard the rest. If you are doing serious research on a specific topic, advanced searching is a betteroption. Well-prepared searches will eliminate useless hits and wasted time. learn how to use a search engine properly to limit the search results tofind only the information which is really relevant. http://sct.emu.edu.tr/it/itec229

2.3 Searching Techniques http://sct.emu.edu.tr/it/itec229

2.3 Searching Techniques • Other techniques you can use to improveyour searches include the following: • Use specific nouns. • Put the most important terms first in thesearch text. • List all possible spellings, for example, email,e-mail. • Before using a search engine, read its Helpinformation. • If the search is unsuccessful with one searchengine, try another. http://sct.emu.edu.tr/it/itec229

Thank You ! Searching the Web http://sct.emu.edu.tr/it/itec229 END of CHAPTER 2

Searching the Web