1) Can someone give me a quick rundown on the file structure of the Droid (or point me to a good explanation)? For example: What are the main system folders? What's in /System or /Data? And what important data is stored on the sdcard, if any? 2) This leads to my next question: when making major OS or ROM changes, my understanding is that it is best to "wipe" one's data, sometimes twice. First off, this is accomplished through the recovery console, doing a factory reset, correct? And, what folders and files are deleted through this process? Is the SD card left untouched? 3) Making a nandroid backup, what is backed-up? Everything including the sdcard's contents or just the core OS files, apps, and settings? Thanks.