Search engine optimisation (SEO) is a part of search engine marketing (SEM) and it requires complete understanding of search engine algorithms and their workings. Today almost all webmasters are performing search engine optimisation methods to improve websites, so that the visibility of the website is improved when a search is performed with a related keyword. If a website is ranking higher for specific search results, it will deliver high volumes of traffic to the website. The traffic delivered through natural search engine queries is high quality traffic and it is also known as organic traffic.