Since Windows 7, your operating system (OS) is preloaded with the software you need to create a duplicate of your drive or image your drive. This feature helps to ensure seamless recovery from a catastrophic failure. All you need a backup target or an external drive.
Purchase an external drive that offers the following, especially if you store confidential information on your source drive (the drive in your computer):
1. AES 256 bit hardware encryption (faster and less dependent on your CPU to encrypt and decrypt)
2. A drive that matches the form factor (physical size) of your source (this way you can simply swap drives in the event of a catastrophic failure)
3. Solid State Drive (faster and rugged)
After you create a system image, you can restore the image to a new hard drive in the event of a catastrophic failure, and you can continue working where you left off (as of the date of the backup) as though nothing happened.
However, if you only backup data, you would have to reinstall your operating system, device drivers and programs on a new hard drive before you can resume working.