U.S. Presidential Election

I went to India recently and all people ask is about the Presidential Elections. I could not answer 99% of their questions because I was not knowing about the elections here. I was not even trying to know about it.

Coming back to US, I started searching for some good article that could explain me the election procedures right from scratch. Yep! I found one. I am providing the link for people like me who have "Zero" knowledge about elections. Here, it is,

http://bensguide.gpo.gov/9-12/election/primary.html