Backing up your files means making a copy of your photos, documents, and other important things so they are not lost if something goes wrong. Hard drives fail, computers get stolen, and accidents happen. A backup means you can get everything back.
What Should I Back Up?
The most important things to back up are the files you cannot replace:
- Family photos and videos
- Important documents like tax returns, contracts, and medical records
- Work files you have created
- Contacts and address books
You do not need to back up programs like Microsoft Word or your web browser — those can be reinstalled. What matters is the files you created yourself.
Sync Is Not the Same as a Backup
Important: cloud sync copies changes, so it is not a backup on its own. If you delete a file, or a file is damaged or encrypted, that change can be copied to the cloud too. Check the trash or version history in your cloud account, if it has one, to recover earlier versions. Keep a separate copy, such as on an external drive, that is not linked to your everyday files. For a longer explanation, see the guide ‘How to back up your photos properly’.
Option 1: An External Hard Drive
An external hard drive is a small device you plug into your computer with a USB cable. You copy your important files onto it, then store it somewhere safe. They are inexpensive and easy to use. The downside is that you have to remember to do it, and the drive needs to be somewhere other than right next to your computer (in case of theft or fire).
Steps for an external drive
Names and screens vary by version and device, so look for similar options if the names differ.
- Plug the external drive into your computer using its cable. Your computer should recognise the drive and show it in its list of drives.
- On Windows, look for the built-in backup option in your settings (names vary by version). Choose the important folders you want copied, and set Windows to copy them to the drive. Once this is set up, Windows should start copying the folders you chose.
- On a Mac, plug in the drive. If your Mac offers to use it for backups, accept, and let the first backup run in the background.
- Wait for the first backup to finish. Then open a few of the copied folders on the drive and check that your files are there.
- Unplug the drive when the backup has finished.
Option 2: Cloud Storage
Cloud storage services can keep copies of your files online. Once you set them up, new changes are copied automatically. Most offer some free storage and charge a small monthly fee for more space.
Steps for copying files to a cloud account
Names and screens vary by service, device and version, so look for similar options if the names differ.
- Use a cloud service you already have an account with, such as one linked to your phone or email account. Many people already have some free space this way.
- Install the service’s app on your computer and sign in with your existing account. Once you are signed in, the app should create a cloud folder on your computer.
- Put a copy of each important folder into the cloud folder the app creates, for example by dragging it in or using the app’s upload option. Copying leaves the originals where they are. The app should then start uploading the copies.
- Wait until the app has finished uploading before you rely on the copy.
- Sign in to the service’s website and check that your important folders and files are listed there.
- Turn on any extra sign-in protection the account offers, such as a second sign-in step.
Option 3: More Than One Copy
The safest approach is to keep more than one copy. A common rule of thumb is the 3-2-1 rule: keep three copies of important files, on at least two kinds of storage, with one copy kept in a different place. For example, keep the original on your computer, a copy on an external drive, and a third copy on a second external drive that you keep in a different place from the first.
How Often Should I Back Up?
If you use cloud storage, check from time to time that your important files are there, because sync is not a backup on its own. If you use an external drive, aim to back up at least once a month — more often if you work with important files regularly.
When to Get Professional Help
If an external drive clicks, makes grinding noises, is not recognised by your computer, or will not open its files, stop using it. Do not keep reconnecting it to test it, and do not open the drive case yourself. Get help from a computer repair service or the drive maker’s support. If you cannot get into a cloud account, contact the provider’s support for help getting back in.
Starting a backup habit today takes less than an hour to set up, and it is one of the most valuable things you can do to protect your digital life.
Last updated: October 9, 2026