Whenever you enter a query in a search engine and hit 'enter' you get a list of web results that contain that query term. Users normally tend to visit websites that are at the top of this list as they perceive those to be more relevant to the query. If you have ever wondered why some of these websites rank better than the others then you must know that it is because of a powerful web marketing technique called Search Engine Optimization (SEO).

SEO is a technique which helps search engines find and rank your site higher than the millions of other sites in response to a search query. SEO thus helps you get traffic from search engines.

This SEO tutorial covers all the necessary information you need to know about Search Engine Optimization - what is it, how does it work and differences in the ranking criteria of major search engines.

Search Engine Basics

Processing queries: When a request for information comes into the search engine, the engine retrieves from its index the entire document that match the query.

Ranking results: Once the search engine has determined which results are a match for the query, the engine's algorithm (a mathematical equation commonly used for sorting) runs calculations on each of the results to determine which is most relevant to the given query.

Directories:

Human edited search indexes

Yahoo Directory!

DMOZ = The Open Directory Project

Search Engine Results Pages (SERPs)

Organic: Results based on content and keyword relevancy (as per algorithm)

Paid Placement (PPC):

Google Ad Words

Yahoo! Search Marketing (YSM)

Why you should use SEO

Brand awareness – A web site having a high ranking means more people see the name of the company and become familiar with the company and its products, even if they haven’t made a purchase.

Targeted traffic – Search engine optimization brings paying customers to your door step. The customers that SEO services bring you are long for your products/services as they have entered your websites keywords/phrases into the search engines.

Your competitors – Keeping ahead of your competition in the organic search results can help boost the perceived position of your company in your marketplace.

How it Works

Search engines, such as Google, Yahoo!, and Bing, scour the World Wide Web. Their automated "robots" (also called "spiders") move from page to page and site to site by following links. Along the way the read the code for the pages they visit. The information from the page code is incorporated into the search engine's vast knowledge base.

When a visitor to a search engine enters a term or phrase into the search box the term or phrase is compared to the information in the engine's knowledge base. The results that are returned (called "organic results") are listed in order of how well they match the term or phrase that was used to initiate the search.

The comparison is accomplished by algorithms. The specifics of the algorithms are closely guarded secrets of the search engines. Apparently, the algorithms vary from search engine to search engine. However, the techniques that we discuss here are applicable to all the engines.

The closer the Web site matches the search term, as determined by the algorithm, the higher it will appear in the list of organic results. The goal of search engine optimization is to help the Web site and its pages rank as high as possible in these organic results.

It is important to remember that search engines sell advertising on their sites. Which ads appear on the results page are also determined by sophisticated algorithms, and are based on the comparisons with the search terms. Your organic result placement will compete with these ads. The better your search engine optimization, the better your placement in the overall results.