I'm new to the whole mobile thing, so I've been looking around but I've been having some trouble determining exactly how rooting manifests to the user. I've seen references to 'su' in the tutorials which leads me to believe that the process enables a root account, but I see no reference to setting a password.

So my question is, is it possible to control tightly what apps get root and what can't? can I prevent malware and bad apps from abusing this privlege, whilst granting me and knowngood apps root happiness? is there an interactive sudo\gksu\kdesu kinda layer for invoking root, or is it more like editing your sudoers?