re: General questions about rooting.

If you know what you are doing, rooting shouldn't cause you any problems (there are all in one toolkits that automate the process for pretty much any phone worth having, like the m8). Rooting simply refers to gaining the ability to modify the root directory of the phone. This is where the system files are. Rooting allows you to use certain backup programs, ad blockers, and to mod your phone in some cool ways. You can make your at&t phone stop playing a loud obnoxious mp3 every time you fire it up or allow the phone to tether without a plan. All in all, it is all about being able to customize like you might do on your pc or laptop.