Is the technique of influencing the visibility of a website or a web page in a search engine’s unpaid results—often referred to as “natural,” “organic,” or “earned” results. In general, the higher (that is on the first page results), and more frequently (on the basis of keywords) a site appears in the search results list, the more visitors it receives from the search engine’s users. SEO may target different kinds of search, including image search, local search, video search, academic search, news search and industry-specific vertical search engines.