What is SEO. How Many type Of SEO?

SEO Stand for search engine Optimization. SEO main motive is increase the Keyword ranking of website. SEO mainly two type On page SEO and Off page SEO. On Page SEO use the Proper meta title, Meta Description, Meta Keywords, Sitemap.xml, Robots.txt etc. Off page activity are the Article submission, Classified submission, Forum Profiles, Yahoo answering etc.
SEO, every website looks for SEO, which leads to the increase in the rank on various search engines like Google, Bing, Yahoo, etc. Through this process, one can create a visibility of a website or a webpage on a search engine, without paying anything to the search engines. The types of Search Engine Optimization techniques use various algorithms, so that the website appears frequently and ranks higher on the search results and hence has more visitors on the website.
White Hat SEO– White Hat SEO uses the techniques and guidelines of a search engine, wherein any content uploaded on the website should have relevant tags and headlines, through which a visitor should return to the website consistently.
Black Hat SEO– Black Hat SEO refers to an aggressive way of utilizing different type of SEO strategies, in a way where focus is mainly on the website rather than on human audiences. It does not usually obey to the guidelines or rules of a search engine
Grey Hat SEO– As the color suggests, this type of SEO technique comes somewhere between the Black and White type. So while considering different type of SEO as well, this type comes between White and Black Hat types of SEO. It uses techniques like three way link exchange, article spinning, buying of old domains, buying expired domains and at last Google Bombing also.