Contents of this tutorial:What is SEOWhat is the need of search engine optimization in websiteHow search engine search and shows the content to the userTypes of SEO – White hat SEO and techniques – Black hat SEO and techniques – Grey hat SEO and techniquesEvolution of Google SEO AlgorithmsWebsite designKeyword ResearchLink building techniquesOn Page SEOOff Page SEO What is SEO:From the term SEO or search engine optimization, we can get the basic idea behind it. SEO is the nothing but the process of optimizing the website to make it friendly and easy grasping by search engines. What is the need of search engine optimization in website:You may wonder, we are writing the contents in website for users then why it is essential to make the website optimized for search engines. Of course, it is mandatory because search are the bridge between users and the websites. So first the search engines should understand that your website has the correct contents to show upon user requests. Here you may have one question, so how should I design and develop the website user friendly or SEO friendly?Answer is Simple : Both. If you make your websites SEO friendly obviously it will user friendly.How search engine search and shows the content to the user:As I already told, search engine is a connecting bridge between user and website so it is important to understand how the user requests are interpreted and shown on the search results.1)Usually, search engines sends the small piece of codes called crawler or spiders in order to fetch the web pages of the website. This process is called CRAWLING. Must read : How to make Google to crawl my site?2)Once the web pages are crawled, then those pages are been processed to identify the keywords of that page. Then those web pages will be indexed on the search engines database for future retrieval. This process is called INDEXING.3)Now your web pages are available in Search engine database, but not only your web pages are there so many other web pages are also crawled and indexed. When the user enter the requests in search engine like Google or yahoo or whatever it is, request string will be processed and compared with indexed keywords. It will fetch the results matching the criteria, but upon which has to be shown first will be based on relevancy web pages. Finally the results will be shown to users.