Jailbreak is Easy if you know how to do xD

iOS jailbreaking is the process of removing software restrictions imposed by iOS, Apple Inc’s operating system, on its devices including the iPhone, iPod touch, iPad, and second-generation Apple TV. Jailbreaking is done by using software exploits, and it permits root access to the iOS file system and manager, so applications, extensions, and themes unavailable through the official Apple App Store can be downloaded.

Jailbreaking in general means breaking the device out of its “jail”, a metaphor used in Unix-style systems, for example in “FreeBSD jail”. A jailbroken iPhone, iPod touch, or iPad running iOS can still use the App Store, iTunes, and other normal functions, such as making telephone calls. Furthermore, a jailbroken device can be reverted to a standard ‘jailed’ device by restoring the device in Recovery Mode.

Jailbreaking is a form of privilege escalation, and describes privilege escalation on devices by other manufacturers as well.