How do advertisers know so much about me?

So I was sitting in front of the computer just doing some typical browsing when all of a sudden I see this advertisement load on the screen. Turns out, its for a site called Shaadi.com. For those who aren't Indian (which I guess in the grand scheme of things isn't a lot of people but if you really sit down and think about it, you notice that there are a lot of Indians so yeah watch out China, we've almost caught up), it's kind of like (and by kinda I mean is most definitely like) Chemistry.com or Match.com or any of those online dating sites except this ones specifically for Indian people.

The ad itself isn't very big. Its about 10 inches long and 3 inches wide so it takes up a good amount of the screen. The tagline for the ad reads "Celebrate the joy of marriage" and then underneath it is an Indain girl in her mid twenties dressed in traditional Indian dress.

The first thing I thought when I saw this ad was, wow, if I ever have to use the internet to find a girl to marry, well then hell I ain't gettin married. Then it hit me. How the hell did Yahoo! Sports know I was Indian. I was logged into my email account but its not like when I signed up for Yahoo! Mail all those years ago, that I had checked a box for being Indian. Was the internet somehow extracting my racial information from the sites I go? I mean I guess Indian people do love Yahoo! (just like how they love Japanese cars, specifically Honda and Toyota, and BK Coffee) but I mean cmon, doesn't everyone love Yahoo!.

But I guess its not just Yahoo! thats in this game of extraction because it seems though Google is somehow in on the game as well. For all who don't know, Google I guess has merged with Blogger.com since you know have the ability to sync your Gmail account with your Blogger account. I enjoy using Blogger since its easy to use and has a nice "aura" to it. It is also very user friendly and includes a toolbar above your text box where you type your post. Well turns out, Blogger is so user friendly that next to my "Remove Formating From Selection" button (which evidently is not an eraser but oddly looks like one) is a button that allows me to type in Hindi, a language I have no idea how to speak.

Thanks Interwebz for making me feel at home and thanks Rod Benson for making me take notice, I hope you play for the Nets soon.