In html if you want to make a word bold you might add a tag to it.
A tag is invisible to the reader but visible to the browser.
I want to make this word bold
I might write an article its in something called a div or division
All the words in the article
yada yada yada.
Google knows nothing special about it.
but if its marked up correctly with the correct titles and etc they know what it is
Human Readable Article Title
Roberto Soto
12/12/12
12/12/12
All the words in the article
yada yada yada.
Google reads it and says its an article its a written by so and so on this date
Other tags would tell it genre, category etc.
Is it approved for people like me that only want GOOD articles
Then as Google moves forward to this kind of stuff in the future
the stuff will stand out and be on the first few pages of search results
will be the articles and other content marked up their articles correctly.
with all this hidden crap.
The others with plain text will be in the dust.