Searching Stackoverflow on Google I get this result:
Inspecting the HTML source of the Stack Overflow frontpage I can't find any reference of
"A language-indipendent collaboratively edited question and answer site for programmers" stuff.
I thought it was something related to meta description, but it is not true.
Also, where are the Log In, Questions, Ask Question etc. declared? Sitemap.xml?
In few words, could I obtain the same result simply editing my web site content, or is it something configured on some Google webmaster panel?