Plus Why Operating Systems Are Like Onions
How to Root an Android Phone | Simple One-Click Rooting Guide [English]
If you've ever encountered a message on your computer or other device stating that you need elevated privileges, you need "root access."
Operating systems must strike a balance between letting users do what they need to do, but without messing up the entire system. For better or worse, if you have "root access" to a computer, you have the keys to the kingdom.
Operating systems (OSs) have layers, just like an onion. Unlike an onion, however, operating systems have kernels.