SEO techniques is one way or another help to market the services of business or your site. The techniques can help produce traffic and to increase the page rank.
SEO can make your web page content more relavant, more attractive, and more easily read by search engines and crawling and indexing softwares.
Whenever you enter a query in a search engine , 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 cheaper and best process to get keyword ranking on SERP in compared to SEM. In SEO ur cost is one time but time taking.