What is Search Engine

Search engine is a program that allow user to search anything on internet. The user search for a specific keyword and getting a list of results by search engine. Its database contain all indexed sites and a program called robot or spider is use this database for provides search result to the user. Some search engines are has database and maintain it by using a algorithm and some search engines are directory based maintained by humans. These directories are called human edited directories.

Hundreds of search engines are on the internet but mostly used search engines are Google, yahoo, MSN (live.com), ask.com, AltaVista, AOL etc. search engine maintain sites in database according to sites priority and value of the information that site contains. Every search engine gives the rank to the site according to his algorithm. Search engine is only way that can get your site at 1st search result page or take it at the last.

When you enter a search keyword in search bar, the search engine spider match your keyword to all database and then choose the best results and show it in search results. It shows only indexed websites that are in its database.