If you're in Europe or North America, you've probably seen the same old plodding cows— wide hips, big eyes, fuzzy ears, and sometimes horns. They're generally a certain color, and have a certain look that just makes them cows.
(I should stop now and note that I'll also be talking about water buffaloes, which aren't cows but are close enough).
In India, cows are sacred. Hurting a cow is unthinkable. If you've ever watched the movie Outsourced, there is a scene where Todd explains that one of the products they are selling is used for branding beef hamburgers. The expressions on the call-worker's faces say it all.
Cows here have horns— long horns, like antelopes, straight and pointing upward (it makes you realize how interrelated animals are), horns that curve out and then in. People paint their horns bright red or bright blue, or put flowers on their heads, or put red paint on their foreheads in that bindi-like dot that most people wear.
They have humps— right above their withers, that at the beginning looked really strange, but now just seems natural. As a side note, you can quite literally get used to anything, even cold and heat (though I refuse to believe it). The cows in India also have ruffs— I don't know what else to call them— basically what they are is hanging skin below the neck. Literally flabs of skin. This, too, is strange, but we got used to it.
Cows are white and dark brown and light brown, sometimes with flecks of white everywhere. They lay in the middle of the street, amble throughout the temples (where people sometimes pass by and pat them), eat the soft inside of green coconuts, banana peels, and anything else they like that's on the street. They'll be stretched out every once in a while, chewing their cud, or being herded along, or squeezing through the back streets.
The water buffalo are different animals. We saw them in Nepal more than here, but basically what they are is big, hairy, fat cows that are black and coarse. They have smaller eyes, wider noses… all in all they're not as beautiful as cows. (And if anyone ever calls me a cow… I think I'll thank them. Their eyes are so amazing! And even their mouthes are beautiful. I understand why Hindus respect them so much). While I don't think I could be afraid of a cow unless it was charging me… water buffalo just look mean. It's not like bison, who look rather wise, or cows, who look motherly… water buffalo look a bit mean and evil. I haven't seen many other bovines in order to speculate on what they look like. (The ones with long, straight horns, though? They just look amazing.)
I'll try and get a hold of some pictures in order to illustrate what each type of cow/buffalo looks like, in order to better illustrate it. ^_^