If you've used JPE before, but are new to this version, the latest version's feature set is available, along with some screenshots and a simple getting started walkthrough to get you familiar with the basics.
JPE attempts to help you solve a very simple problem, in theory, but one that is hard, in fact, to overcome. How do you take (physically or virtually) the same set of apps, and their associated settings, and/or any associated user data, with you from pc to pc, and/or from data storage device to data storage device, and/or from user account to user account, and/or from pc rebuild to pc rebuild, etc., by the simplest means possible?
Some apps are written this way - to be portable. A large number of useful apps, however, are not. Which is where JPE comes in. It attempts to make a non-portable app behave as if it were written to be portable. It does this through the use of four major components: the JauntePE app itself (the gui), a portable content package, an app launcher, and a runtime code library.