The first method in learning how Jailbreak iPhone works is by obtaining root access to the iPhone so that you will be able to install softwares provided by third parties not supported by Apple. This is similar to the unlocking performed on the iPod Touch. This type of unlocking is also referred to as “jailbreaking”. This method allows you to make personalized ringtones which are in contrast with using only the ringtones in iTunes that comes with additional cost and functions only on music purchased in iTunes.
The second method of unlocking is by firmware modification which enables your iPhone to accept other SIM cards provided by other mobile networks. There are free solutions available that will perform the unlocking of your iPhone.