Search Engine Optimization (SEO) is a part of search engine marketing. SEO is the process of improving the number and quality of visitors to a website. Ranking high in the search results of search engines does this. If a web site ranks high in search results that website will be visited by more number of visitors. It is essential for a site to rank high in order to direct more visitors to the site as many of them ignore to visit every page of search result. Search engine optimization ensures that a website is accessible to search engines.
Search engine optimization began in the mid 1990s. Search engines uses programs called “spiders” that crawls a page and store the information on that page. This comprises the contents on a page and some codes used to build the page. Generally, the contents and basic codes that the spiders search for on a page include recommended articles, article archives, discussion forums, reports and books.
Recommended articles are articles that try to explain the key concepts of the topic given. Each article can be opened in a new window. Article archives contain a list of thousands of search engine articles. Article archives arrange articles by date and this helps the visitor to get the latest information. Discussion forums contain the page element being discussed. If there are books and reports that cover the page element being discussed are available, it will also be included.
Earlier webmasters themselves used to supply information about the pages to the search engines. Meta tags provided by webmasters directed the users to contents of each page. But this was found to be less reliable since webmasters mistreated Meta tags by adding keywords that is not needed in the contents of their pages. This was done in order to falsely increase page impressions for their website and there by increase their Ad revenue.
Abuse of meta tags by webmasters made search engines to develop more complex ranking algorithms by including additional factors such as text within the title tag, domain name, HTML tags, URL directories, file names, term frequency, keyword proximity, keyword sequence, keyword adjacency, all attributes for images, web content development, text within NOFRAMES tags and sitemaps. These factors were also under the control of webmasters and search engines continued to undergo abuse and ranking manipulation. This led to the birth of a new search engine, Google.
Google introduced the PageRank concept to assess web pages. This algorithm evaluated the importance of web pages based up on the incoming links. With the effectiveness of PageRank algorithm, Google came to be considered as the most reliable and popular search engine.