Evolution of Search Engines
What Is Search Engine
A search engine is a program available over the internet that searches for the document and files correspond to keyword specified by user and return the result of any file containing these keyword. the first ever search engine developed is an archie and is used for searching the FTP files. The most popular search engine now-days is Google. Many other search engines available in market includes Bing, Yahoo, Ask.com, AOL, Baidu etc.
HOW DO SEARCH ENGINE WORK
Every search engine has 3 main function
This is the first step in understanding the working of a search engine. It is a process of scanning and collecting information about every page But how’s the Crawling done? An automated bot visits page after page as quickly as possible, using page links to find where to go next. Google’s spiders could read several hundred pages per second in the earliest days. Nowadays, it’s in the thousands. any site that is linked to a indexing site will be crawled automatically. When a web crawler visit a web page it collect all the links from the page and add them to its list of next visiting page. Web crawlers also revisit past pages once in a while to see if any changes happened.