How does Google use HTML tags to enhance the search engine?

Question

I know that Google’s search algorithm is mainly based on pagerank. However, it also does analysis and uses the structure of the document H1, H2, title and other HTML tags to enhance the search results.

What is the name of this technique "using the document structure to enhance the search results"?

And are there any academic papers to help me study this area?

The fact that Google is taking the HTML structure into account is well covered in SEO articles however I could not find it in the academic papers.

Answer 1

I think it's called "Semantic Markup"

[...] semantic markup is markup that is descriptive enough to allow us and the machines we program to recognize it and make decisions about it. In other words, markup means something when we can identify it and do useful things with it. In this way, semantic markup becomes more than merely descriptive. It becomes a brilliant mechanism that allows both humans and machines to “understand” the same information. http://www.digital-web.com/articles/writing_semantic_markup/

A more practical article here http://robertnyman.com/2007/10/29/explaining-semantic-mark-up/

Answer 2

SEO has become almost a religion to some people where they obsess about minutiae. Frankly, I'm not convinced that all this effort is justified.

My advice? Ignore what so-called pundits say and just follow Google's guidelines.

You might be looking for an academic answer but honestly, this isn't an academic question beyond the very basics of how Web indexing works. The reality of a modern page indexing and ranking algorithm is far more complex.

You may want to look at one of the earlier works on search engines. Note the authors' names. You may also want to read Google Patent application 20050071741.

These general principles aside, Google's search algorithm is constantly tweaked based on actual and desired results. The exact workings are a closely guarded secret just to make it harder for people to game the system. Much of the "advice" or descriptions on how Google's search algorithm works is pure supposition.

So, apart from having a title and having well-formed and valid HTML, I don't think you're going to find what you're looking for.