Casper creates a complete copy of your system hard disk, including the operating system, applications, settings, and all of your data. The Ideal Backup Solution for Windows Casper makes it easy to keep a complete and instantly bootable backup replacement hard disk for your system. Should your system hard disk fail or become corrupted by a virus or spyware attack, you can boot and run your computer directly from your backup hard disk and be up and running again in seconds!