Veterinary Consultant, Dr. Keith Webb, says a search engine is a device that delivers contents to you as per your query from the World Wide Web. Search engine locates the suitable content from the plethora of information available on WWW in form of links, images and web pages. These engines are based on complex algorithms and sometimes even on human editing.
Web crawling, indexing and searching combine in that order to obtain the most accurate results. Mass amounts of information on millions of web sites are stored and then retrieved relevant to the user’s request. A web crawler is also known as a spider, it analyzes every link and indexes all information for faster retrieval.
Mata tags and even words from the webpage are studied to classify the webpage and its content. All these data are stored for future usage.
All the search engines work on more or less the same principle. Google stores the source pages, also called cache, of all the web pages along with information available on the webpage itself. AltaVista differs slightly in operation as it stores everything that a web page has on offer.
Search engines will examine keywords entered by the user and obtain a list of organized search results. Summaries may also accompany web links on the results page.
The goal of major search engines is to supply the most relevant results. Not all sites with the requested keywords are relevant to the search. The search engines have used their spiders and indexing to filter out useless information. They generate their own system for analyzing a website for content.
Page rank is latest addition in the techniques used by search engines to sort out various web pages and their contents. Page rank decides the relevance of a particular page by studying the correlation between its meta tags, descriptions, keywords used and the content of that webpage. The search engines rank those sites high that have association with high ranked web pages. The page rank is essential for any web page or site as it determines its probability of featuring at the top of any particular search.