A keyword is a word or a word combination mentioned in the text of a website and bearing essential meaning, which reflects the page content the most precisely. SEO is carried out considering the definite keywords, and the website’s position in search engines output depends on how well the website is optimized for the keyword mentioned in the search query.

There are commercial, informational and reference search queries. It is necessary to understand clearly what sort of quiries are necessary for the website as this influences the keywords selection.

Selection of the keywords (the semantic kernel composition) is an important stage of SEO, which defines the further promotion strategy and can affect the optimization cost considerably. Some keywords are easier than other to get on top by in the search engine result pages.

At the keywords selection stage, the approximate number of visitors which the website can get in case of being in the output top positions on a certain keyword can approximately be defined.