Is it bad to crack your back?

i was just wondering this question because I do it almost every day and a lot of my friends do it.

its not at all good for u
my grandma did and the doctor said because of that is why she gets back aches and pains
well good luck:)

It's not the best idea to do this without advanced anatomy knowledge... It can lead to conditions such as arthritis. There's more here:
http://www.wisegeek.com/why-does-it-feel-good-to-crack-your-neck-and-back.htm