When I first joined the boards here, I had no idea what rooting was.... I also did not understand "flashing ROMs", "overclocking", etc etc. In the simplest of terms; it's like using a public computer at the library (people still go to libraries, right?). You can do a lot of things on it and complete any one of a large number of basic tasks, just like your Droid, out of the box... tons of functions and access and so on. But on those same computers, if you try making changes to Windows folders or performing control panel tasks and so on, it won't let you, and will say you need "administrator access". Droid is the same way. There's only so much you can edit on the phone normally. Rooting is essentially your way of giving you that administrator access so you can change more aspects of the phone that you otherwise wouldn't have access to.