The Internet consists of millions of private/public/academic/business and government networks having local to global scope. It has billions of web pages on varied topics that may be accessed by you. Thus, if you are asked to surf the net for specific information relating to a topic, it may take years before you could find all the pages related topic you are looking for. How can you make this process faster? Well perhaps you require the service of a search engine on the Internet. Some of the popular search engines on the Internet are: Yahoo!, Google, Bing, Ask.com and many more. These are the tools to help you locate the content that you are looking for.
A search engine can be defined as a tool to search diverse and disorganized sources of information available on the Internet. You can clearly visualize from this definition that a search engine has to use some automated programs that needs to continuously keep visiting the web pages about the content they have and organize the information about web pages in some format. Programs that continuously keep searching for information from web pages are called -spiders, robots, crawlers, wanderers and worms. Search engines finds, classifies and stores information about the contents of various websites on the