Keywords are at the very core of every effort at search engine optimisation. This is because people may not know it but every time they type a word or a phrase in the search field of any search engine, this triggers a chain of reaction in which all contents with such words will appear in the results. Whatever they type are actually the keywords. Because of this, it is very important for an online marketer to use the right keywords in the contents that he is going to use for SEO. If the wrong keywords are used, his website or the contents that he made will naturally not appear on the results pages of the search engine. As a result, his SEO effort may well be considered as a failure. Due to the importance of keywords, online marketers and SEO experts have often spent more time and effort in this.