Saturday, 2 June 2012

Web Browsing

What is web browser?

1. A web browser is a software application that enables a user to display and interact with text, images, and other information typically located on a web page at a website on the World Wide Web or a local area network.

2. Software that displays web pages

3. Software that gives a user access to the World Wide Web. Web browsers often provide a graphical interface that lets users click buttons, icons, and menu options to view and navigate Web pages.

What can you do with web browser

– Browse web pages if you know the URL
• e.g
• http:/
– Search the web using
• Search tools
– Search engines
– Subject Directories
– Name Directories
– Meta‐Searchers
– Specialized Search Tools and Searchable Databases

Search Tools : Search Engine
1. Software that enables users to search the Internet using keywords.
2. A search engine is a computer program that does the following:
  • allows user to submit a query that consists of a word / phrase
  • searches the database
  • returns a list (hits) that may consist of web pages, images, information and other types of files which match the query
  • allows user to revise and resubmit query
Example of search engines:
1. Google : ,
2. Yahoo! Search :
3. AltaVista :
4. etc!

How search engine works?
The search engines maintain databases of web sites
use programs ("spiders" or "robots") to collect information,which is then indexed by the search engine.
• Similar services are provided by "directories," which maintain ordered lists of websites, eg Yahoo!
Computer software program designed to help users of the Internet locate information on the World Wide Web. It collects and indexes Internet resources ( Web pages, Usenet Newsgroups, programs, images, etc. ) and provides a keyword search system allowing the user to identify and retrieve resources. There are many search engines available and each is different in their scope, search protocols, and appearance. Some common search engines are: Alta Vista, Google, Yahoo, Excite, Lycos, and HotBot...

Search Tools : Directories

• Subjects
  • built by human selection ‐‐ not by computers or robot programs
  • organized into subject categories, classification of pages by subjects ‐‐ subjects not standardized and vary according to the scope of each directory
  • NEVER contain full‐text of the web pages they link to ‐‐ you can only search what you can see (titles, descriptions, subject categories, etc.) ‐use broad or general terms
  • small and specialized to large, but smaller than most search engines ‐huge range in size
  • often carefully evaluated and annotated (but not always!!)
  • Subjects
    – Google Directory :
    – Yahoo! :
    – Librarians' Index :
    – Infomine :
    – Academic Info :
Search Tools: Meta‐Search
Search more than one search engine and/or subject directory at once and then compile the results in a sometimes convenient display, sometimes consolidating all the results into a uniform format and listing.
– E.g. :
• Dogpile :
• Metacrawler
• Tripleme

Other search tools

• Local Search / Maps
• Mobile Text Search
• Desktop Search
• Google Special Searches
• Audio/Video/Imej

Web Browser: Search techniques

– Use subject directories.
– Use implied and full Boolean logic, phrase searching, truncation, and field searching effectively.
• Boolean "operators" such as "AND," "OR," "AND NOT" and sometimes "NEAR." AND requires all terms appear in a record. OR retrieves records with either term. AND NOT excludes terms.
 – Identify key concepts, synonyms, and variant word forms in your search topic.
– Use phrase
• More than one KEYWORD, searched exactly as keyed (all terms required to be in documents, in the order keyed). Enclosing keywords in quotations " " forms a phrase in Google , and some other search tools.
– E.g “educational technology” / educational technology will give different results
– Use key search engines effectively including AltaVista, Google, All the Web/FAST, and HotBot etc…
– Use meta‐search engines.
– Use specialty databases when appropriate.
• Social sciences:
– Apply search strategies and techniques in a scavenger hunt exercise.

No comments:

Post a Comment