Your laptop stops working. You take it to a repair shop and they say the hard drive is dead — they can try to recover the files, but it will cost several hundred dollars and there is no guarantee. You think about what was on that laptop: tax documents, photos from the last five years, a folder of important receipts, and a half-finished report you need for work next week.
A backup is a copy of your important files stored somewhere other than your main device. If your computer breaks, your phone is lost, or your files get accidentally deleted, the backup gives you a way to get them back. It does not prevent the problem — it makes the problem recoverable.
What to back up
You do not need to back up everything on your computer. Focus on files that would be difficult or impossible to replace:
Personal documents. Tax records, insurance policies, lease agreements, medical records, identification documents.
Photos and videos. Especially ones that exist only on your device — photos from your phone that are not in a cloud service, videos from family events.
Work files. Documents you have created, reports, presentations, and anything your employer does not already store on a shared drive.
Financial records. Bank statements, receipts for major purchases, warranty documents.
You do not need to back up apps, software installers, or files you can download again. Focus on the things that are unique to you.
The simplest backup: cloud storage
If you already use a cloud storage service — a service that stores files on the internet and syncs them across your devices — you might already have a partial backup. Files saved in your cloud storage folder are backed up automatically.
The key word is “if you saved them there.” Many people have files on their Desktop or in a local Documents folder that are not synced to the cloud. Check your cloud storage folder and compare it to the files on your computer. If important files are only on your computer, move copies into the cloud folder.
Cloud storage is convenient because it happens automatically once you set it up. The downside is that it requires an internet connection and a subscription if you need a lot of space.
The second backup: an external drive
An external hard drive or USB drive gives you a physical copy of your files that does not depend on the internet. This is useful as a second backup — not instead of cloud storage, but in addition to it.
What to buy. A basic external hard drive with enough space for your important files. For most people, a drive with 500 gigabytes to 1 terabyte is more than enough.
How to use it. Connect the drive to your computer, copy your important folders onto it, then disconnect the drive and store it somewhere safe — a drawer, a shelf, or a fireproof safe.
How often to update it. Once a month, connect the drive and copy any new or changed files. You do not need to copy everything again — just the files that are new or different since the last backup.
An external drive is also useful for files that are too large for cloud storage, like video files or large photo collections.
The 3-2-1 rule (simplified)
A common backup strategy is called the 3-2-1 rule: keep 3 copies of your important files, on 2 different types of storage, with 1 copy stored somewhere other than your home.
For most people, a simplified version works:
- The original files on your computer or phone
- A cloud backup — files synced to a cloud storage service
- A local backup — files copied to an external drive stored at home
This covers the most common problems: a broken device (you have the cloud copy), a lost internet connection (you have the external drive), and a house fire or theft (you have the cloud copy stored elsewhere).
You do not need all three from day one. Start with cloud storage. Add an external drive when you can.
What about your phone?
Your phone probably has important files too — photos, notes, documents you have saved. Most phones can back up automatically:
Photos. Enable automatic photo backup in your phone’s settings or in a cloud storage app. This saves every photo you take to the cloud without you having to think about it.
Documents. If you save documents on your phone, make sure they are in a cloud storage folder, not just in the phone’s local storage.
Contacts and settings. Most phones can back up contacts, app data, and settings to the cloud. Check your phone’s backup settings to make sure this is turned on.
A phone backup is especially important because phones are easier to lose or damage than computers. If your phone falls in water or gets stolen, a backup means you do not lose your photos and contacts along with it.
When to back up
Backing up is not a one-time task. It only helps if the backup is current.
For cloud storage: If your files are in a synced cloud folder, the backup happens automatically. Just make sure important files are actually in the cloud folder, not sitting on your Desktop.
For an external drive: Update the backup once a month. Set a reminder on your phone or pick a regular time — the first of the month, or the last Sunday of the month.
After a major change. If you finish a big project, take an important set of photos, or receive important documents, back them up right away. Do not wait for the monthly update.
Related guides
- How to Create a Simple Folder System — organizing your files before backing them up
- How to Name Files Clearly — naming files well so you can find them in your backup later
- How to Keep Work Documents Organized — keeping work files in order so nothing gets missed during backup