When a Search Engine visit your page, it recognize a heading because you are using the <H> tags. One of the most important headings is the H1 tag because is the title of the body of that particular page.
In this case is very important to use your main keyword(S) as part of the H1 tag to let the search engines know that your content is related to your website.
Limit the use of the H1 tag to only one time in the body of your page.
It will add a little bit of weight if you use H2 tags too (with related keywords), it’ll shows to the search engines that your content is tidy and that you put some efford to deliver good content for your readers/visitors.
I most say that the H1 tag is one of the most important aspect of you onsite optimization, after your “title” of course.
Let’s take a look at the next website H1 and H2 tags:
<h1>Britain’s Biggest and Best Car Buyer’s Guide</h1>*
<h2>Reviews, specs and prices for every car</h2>**
*You should only have one H1 tag on each page
**You can have as many H2 tags as you want… or H3, H4,H5,H6 but they have less weight.
Tip: Imagine your website as a book, the tags would be the chapter headings.
That’s it, that will help the search engines to find your site more attractive 
Some people forget those details when they are trying to optimize their sites, but remember that every little counts, if you add all those little details to the equation you will have more chances to increase your ranking.
