How search engine does work?

[mmrsinha]

A search engine is a coordinated set of programs that includes:
++A spider (also called a "crawler" or a "bot") that goes to every page or representative pages on every Web site that wants to be searchable and reads it, using hypertext links on each page to discover and read a site's other pages
++A program that creates a huge index (sometimes called a "catalogue") from the pages that have been read
++A program that receives your search request, compares it to the entries in the index, and returns results to you

[fahad.faisal]

Thanks a lot for the informative post.