What is the 3-2-1 backup rule?

The 3-2-1 rule means: keep 3 copies of your data, on 2 different types of storage, with 1 copy in a different location. This protects you against almost any disaster.

The 3-2-1 rule is the standard recommendation from data recovery professionals. The three copies are: your original files on the computer, a local backup on an external drive, and a cloud backup. The two storage types protect against media-specific failures. If a power surge destroys everything electrical, your cloud copy survives. The offsite copy protects against physical disasters like fire or theft.