Search Engine Optimization (SEO) is one of the most important factors in the last few years that your website is visited from visitors by search engines. Search engines such as Google, Najdi.si etc. … have criteria by which websites ranked in the search result. If you are in the first position your website is very well visited compared to those websites that follow the first position.
So Google has more than 200 different criteria through which determ any web site position. Google criteria also varies with time, as well as the weight of each criterion, is sometimes a more important criteria than the other, it can happen that this also change over time.
Therefore, it is necessary to follow the trend on the World Wide Web.