Leo Laporte has mentioned this rule about backing up computer files a couple times. This week on Macbreak Weekly, he finally gave the website:
The simplest way to remember how to back up your images safely is to use the 3-2-1 rule.
- We recommend keeping 3 copies of any important file (a primary and two backups)
- We recommend having the files on 2 different media types (such as hard drive and optical media), to protect against different types of hazards.
- 1 copy should be stored offsite (or at least offline).
I accomplish this by backing up my computer to both to a USB hard drive and to an online backup service like Mozy.com or Carbonite.
