# How to back up your files properly

A good backup has to survive whatever destroys your original files: a failed drive, theft, fire or ransomware. A copy on the same computer won't.

## The 3-2-1 rule

- **3 copies** of anything important: the original and two backups.
- **2 different types of storage,** such as an external drive and the cloud.
- **1 copy somewhere else,** away from your home or office.

## A simple setup

- **Local:** Time Machine on a Mac, or File History or a backup tool on Windows, running to an external drive.
- **Off-site:** a cloud backup service that runs automatically.

## Is cloud sync a backup?

Not by itself. Services like iCloud and OneDrive are useful, but deleting or encrypting a file can sync that change everywhere. Version history can help, but it has limits. It's best to keep a separate backup as well.

## Test it

Every few months, restore a file from your backup. A backup you've never tested is only a hope, and it's better to find a problem now than on the day you need it.