Quote Originally Posted by Mike41793 View Post
It means you unlock it to get all free apps and stuff. It will void your warranty though so you kinda gotta know what youre doing.
I did it for my itouch but i dont think id wanna do it for my iphone bc that could get expensive if i mess it up haha.
Honestly you can't mess an iPhone up by jailbreaking it. If anything ever happened to it you simply just restore the phone and after restoring the jailbreak is undetectable by apple. Jailbreaking or not, something can always happen to the phones (freezing, bricked etc.) so just be sure to back it up every so often.