^ Yep.
The iPod concept is that you carry around an EXCERPT of your media library in your pocket.
The media library itself lives at home, on your computer.
If anything goes wrong with an iPod - if there's any sort of hiccup, or the software gets corrupted, or *anything* - the first thing that's done is pretty much always to completely nuke the iPod and reset it to factory, then adding back all your media.