I hope you all have some experience with searching over the Internet. Have you ever noticed how these results are organized by the search engines? Have you noticed websites with higher rank or authority comes higher in search results? It is all because of the powerful Internet marketing technique of Search Engine Optimization or simply SEO.

SEO is a technique used for improvising the visibility of webpages in response to a search query. It helps search engines to locate and index your page from millions of other pages having the same keywords. In short SEO is an essential factor for driving traffic into your site.

How search engine works.

A search engine is a program or web interface which is used to collect results and display it based on users search queries. There are a lot of search engines over the Internet. Most popular ones are Google, Bing and Yahoo. There exists a lot of difference between how humans see a web page and search engines see a web page. Human beings can enjoy the style, orientation, design and various ocular aspects. But a search engine only sees the text in the pages. All the flash animations, JavaScript, and pictures are invisible to a search crawler. The whole process takes place in a couple of steps. The first step is crawling

Crawling is the process of visiting a website to check what all are in it. This crawlings are done by computer programmed pieces of codes called spiders or crawlers. These spiders follow each and every link they meet thereby crawling millions of pages all over the internet. Thus crawling helps search engine to find new pages.

Once crawling is done the second step is Indexing .The indexed contents are added to the search engine’s massive database, so that it can be used at a later time. Indexing involves the process of identifying each and every words, expressions and phrases that fits best for the page and assigning them with apt keywords. This seems to be a tedious job to a man, but it can be done easily by the backend software of search engines. A search engine might not understand the context of the article. SEO Plays a vital role in this part. While indexing, proper optimization of the page will help to identify and classify the page with relevant keywords. A properly optimized page helps you earn better rankings.

The next step is processing. Processing comes to play, only when a search request comes. The search engine will compare the search keywords with those inside the indexed pages stored in its database. Since a keyword will be found in many number of pages, it will start to calculate the relevancy  of the pages in its index wrt the search keywords.

The relevancy of a page is calculated with the help of many sophisticated algorithms. Earlier this could be done by just adding a couple of meta tags and a few other things. Currently almost all search engines have their unique set of algorithms and they make changes to the structure periodically. Pages should be adapted to the new changes in the algorithms. So in order to outrank your competitor, your content has to be modified wrt to changes in search engine algorithms. This constitutes a major reason to hire a consultant to do your SEO works.

The last step in search engine activity is to retrieve the results of the pages found in its database and displaying it on a results page.

Most of the search engines work on the common principle of operation, but there exists a lot of differences. Different engines prioritize different values for determination of relevancy of contents. That is the reason for getting different search results in different search engines