Web browser

1. Web browser A Web browser is a software applicationwhich enables a user to display and interact with text, images, videos, music, games and other information typically located on a Web page at aWeb site on the World Wide Web or a local area network. Text and images on a Web page can contain hyperlinks to other Web pages at the same or different Web site. Web browsers allow a user to quickly and easily access information provided on many Web pages at many Web sites by traversing these links. Web browsers format HTMLinformation for display, so the appearance of a Web page may differ between browsers.

2. Web browser Web browsers are the most-commonly-used type of HTTP user agent. Although browsers are typically used to access the World Wide Web, they can also be used to access information provided by Web servers inprivate networksor content in file systems. {A user agent is the clientapplication used with a particularnetwork protocol; the phrase is most commonly used in reference to those which access theWorld Wide Web, but other systems such as SIPuse the term user agent to refer to the user's phone.}

3. Web browser Current Web browsers Some of the Web browsers currently available forpersonal computers include Internet Explorer Opera Mozilla Firefox Safari Avant Browser Konqueror Lynx Google Chrome Maxthon Flock Arachne Epiphany K-Meleon AOL Explorer.

4. Internet Explorer • Windows Internet Explorer (formerly Microsoft Internet Explorer; (commonly abbreviated to IE), is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems starting in 1995. It has been the most widely used web browser since 1999, attaining a peak of about 95% usage share during 2002 and 2003 with IE5and IE6. • The most recent release is version7.0

5. Opera (web browser) • Opera is a web browser and Internet suite developed by the Opera Softwarecompany. Opera handles common Internet-related tasks such as displaying web sites, sending and receiving e-mail messages, managing contacts, IRC online chatting, downloading files via and reading web feeds. Opera is offered free of charge for personal computersand mobile phones, but for other devices it must be paid for • Features of Opera include tabbed browsing, page zooming, mouse gestures, and an integrated downloadmanager.

6. Mozilla Firefox • Mozilla Firefox is a web browserdescended from the Mozilla Application Suite and man aged by Mozilla Corporation • Firefox includes tabbed browsing, a spell checker incremental find, live bookmarking, a download manager, and an integrated search system that uses the user's desired search engine (Google by default in most localizations). • Firefox runs on various versions of Microsoft Windows, Mac OS X, Linux, and many other Unix-like operating systems. Its current stable release is version 3.0.7, released on March 4, 2009.

7. AOL Explorer • AOL Explorer, previously known as AOL Browser, is a graphical web browserbased on the Microsoft Tridentlayout engine and was released by AOL. In July 2005, AOL launched AOL Explorer as a free download and as an optional download with AIMversion 5.9. AOL Explorer supports tabbed browsing

8. Avant Browser • Avant Browser is a popular freewareweb browser from a Chinese programmer named Anderson Che, which unites the Trident layout engine built into Windows with an interface intended to be more feature-rich, flexible and ergonomic than Microsoft's Internet Explorer (IE). It runs on Windows 98 and above, including Windows Vista. Internet Explorerversion 6 or 7 must be installed.

9. Lynx (web browser) • Lynx was a product of the Distributed Computing Group within Academic Computing Services of the University of Kansas, and was initially developed in 1992 by a team of students at the university (Lou Montulli, Michael Grobe and Charles Rezac) as a hypertext browser used solely to distribute campus information as part of a Campus-Wide Information Server. In 1993 Montulli added an Internet interface and released a new version (2.0) of the browser. • Lynx was originally designed for Unixand VMS and is a popular console browser on Linux. Versions are also available for DOS, recent versions run on all Microsoft Windows releases

10. Safari (web browser) • Safari is a web browser developed by Apple Inc.. First released as a public beta on January 7, 2003on the company's Mac OS X operating system, it became Apple's default browser beginning with Mac OS X v10.3, commonly known as "OS X Panther." Apple has also made Safari the native browser for the iPhone OS. • The current stable release of the browser is 3.2.1 (Macintosh) and 3.2.2 (Windows),

11. WEB Browser Detail

12. SEARCH ENGINE • A search engine is a program that helps the internet user to locate information on the www. A web search engine is actually a database that contains reference to thousands of internet resources such as web pages. • The users interact with these database by specifying some keywords such as word or phrase. On the basis of the keyword entered, search engine returns a list of relevant pages from the database that matches the search criteria. • This information may vary from one search engine to another

13. SEARCH ENGINE • Generally there are three main components to a search engine: • Web crawlers: Web crawler is a software that constantly traverse the web to gather information by following the links on the web pages. • Database : All the information that the web crawler retrieves is stored in the database. • Search Interface: The search interface component which is an interface between the end-user and the database helps the user to search through the database. • Some popular web search engines are: • Google • Yahoo • MSN Search • Alta Vista

14. Searching the www • Internet explorer has a built in search facility to perform web searches via the search button on the standard toolbar or by simply typing words into the address bar (auto search). These search facilities helps us to search things easily. • Searching using search button : in order to perform a web search we just click on search button on the standard toolbar in the internet explorer window. • Auto search: in order to perform auto search we go to the address bar and type find India hostels, go India hostels. The internet explorer will automatically send your queries to a search service and display a list of search results. You can choose from the list by scrolling the list.

15. Web Directory • Web Directory is a highly structured way of searching information on the www. A web directory is also known as indexes or catalogues. • Web directories organize there resources using hierarchical tree structure, moving from general structure category to a more specific one. Web directories may be organized in a variety of ways such as alphabetically or topically . • Web directories are hypertext links to present there list resources. When a user click on a particular category in the web browser then he is presented with a series of links to the sub categories. This process continue until you get the desired category of interest.

16. Working of a search engine • Now describe how a search engine works. We split up its functions into a number of components: User Interface, searcher and evaluator. • User Interface: the screen in which you type a query and which displays the search result. • Searcher: the part that search a database for information to match your query. • Evaluator: the function that assigns relevancy scores to the information retrieved. • Gatherer: the component that traverses the web, collecting information about pages. • Indexer: the function that categorizes the data obtained by the gather and creates the index.

17. Metasearch engine meta-search engine is a searchtool that sends user requests to several other search engines and/or databases and aggregates the results into a single list or displays them according to their source. Metasearch engines enable users to enter search criteria once and access several search engines simultaneously. Metasearch engines operate on the premise that the Webis too large for any one search engine to index it all and that more comprehensive search results can be obtained by combining the results from several search engines. This also may save the user from having to use multiple search engines separately.

18. Metasearch engine The term Metasearch is frequently used to classify a set of commercial search engines, see thelist of search engines, but is also used to describe the paradigm of searching multiple data sources in real time. The National InformationStandards Organization (NISO) uses the terms Federated Search and Metasearch interchangeably to describe this web search paradigm.

19. Metasearch engine

20. search engines work Search Engines per definition are information retrieval system designed to help find information stored on a computer system. A search engine consist of three parts First part is the spider which is also called the crawler or bot. This spider part visits a web page, reads it, and then follows links to other pages within the site. This process is often referred to as crawling or spidering.

21. search engines work Crawling of a website is done on a very regular basis, frequency of which is determined by the frequency with which website adds the content. It can vary from once in a month to several times in a day. The spiders visit a website following links from other website or website submission it received. The content that spider find is sent to its database or index as it is popularly known. This index is like a huge book that contains a copy of web page or cache, that the spider finds out. This constitutes second part of a search engine.

22. search engines work It also stores the structure and the way pages are linked to each other. This information would be updated every time there is a change in content or linking. There could be interval between spidering and indexing which varies from site to site and engine to engine. But until indexed, the web page would not be available for the search terms.

23. search engines work Third part of a search engine is search engine software that works behind the interface when we use a search engine. This software will sift through the trillions of indexed pages to match the search query that user has asked. The pages are ranked by search engines and the search results are based on this ranking and relevance to search term. This is how a search engine determines what order shall be listed for a particular search.