Ok so I am student, about to get my degree in computer science. I have been programming for couple of years now on my Macbook pro on OS X and I havent had any problems. On the other hand, everyone around is telling me to install linux OS because its better, developers use it, programmers use it, etc. But no one told me why is linux better than OS X? What's the big deal about having programming and developing on Linux?
It's kind of one of those things you just have to experience to really understand it. For one, the community is really supportive and educated. You don't get as many of the "Why do you even want to know that?" reactions out of Linux users that you do with users/developers of other operating systems. I would suggest just using it for a few months and getting a feel for it to see if you like it.
If you're into EE (going off your profile) you may want to look into embedded systems based on Linux and the options for compiling your own kernel.
There are technical differences but the question you posed is so broad and opinion based that it's hard to give you a definitive answer that's clearly correct whereas other answers are not.