Rooting your phones allows you to flash custom ROMS, which are alternative versions of Android that give you "root" access to all of your phone's functions. Even more importantly, it allows access to data on both your internal memory card and your external SD card. This may be intimidating for some people since those unfamiliar with such technology can be afraid to delete major functionality programmed on your device. But the benefits of rooting your phone can include access to amazing, free apps that only work on rooted devices.