The variables for which a web page, let alone an entire website can compete more or less likely in the organic positioning of search engines in the hundreds.
However, there are some variables that are more important than others. Interestingly, among them there are some that are poorly maintained even though its importance has been demonstrated with sufficient firmness so that was something upscale to tackling the page optimization. One of these variables seldom optimized correctly is styles.
Styles are the H1, H2, H3 codes … and so on that certain parts of the page, usually textual elements are applied and which also served to create infrastructure that communicates the importance of search engine robot.
Thus, the H1 is used to designate the most important part of a page, usually applying to the title of the website or specific page where the user is located at that time.
The H2 is designated to those parts also vital to the web, but unlike the H1 is common use on more than one occasion and for different sections. Usually applied to subtitles, taglines or a second concept is of interest to note the seeker. It is possible more detailed than the H1 alone could not convey explanation.
The H3, like successive styles, down to the level of importance for the search and in theory if applied correctly, facing what is highlighting. Often it used to define the different parts of a web page, so that the final structure remains clearer the robot analyzes the page for specific positioning in search engine results.
Thus, we mainly have one or two H1, an amount normally twice H2 and H3 all necessary to structure parts of a web page properly. Successive styles used for those complex pages where the final infrastructure needs more styles for proper differentiation.
The importance of the H1 and H2 is vital to compete for certain key words, almost the same level as the domain URL or page title. It represents the most important text of the page and is being transmitted to the search engine, hence to be recognition of its real priority in the SEO of a website.