Where should I keep my files — external drive, network drive or cloud?

The choice is usually presented as a product comparison, which is the wrong frame. Each option protects against a specific set of failures and is completely blind to the others, so the sensible way to choose is to list the ways files actually get lost and see which columns cover which rows. That produces the well-known backup rule from first principles rather than as a slogan.

Step by step

1. List the ways files are actually lost.A drive failing. Deleting or overwriting something by mistake, sometimes months before you notice. Ransomware encrypting everything it can reach. Fire, flood or theft taking the whole building. And losing access to an account or a service closing.
2. Be honest about the internal drive.It is the working copy and it protects against nothing. Every failure on the list takes it. That is not a criticism; it is simply not a copy.
3. Understand what an external drive does and does not do.It covers drive failure well and covers a mistaken deletion if the copy predates the mistake. A drive left permanently connected is reachable by ransomware exactly like the internal one, and it is in the same building, so fire and theft take both.
4. Judge a network drive on what it actually adds.Capacity, access from every device in the house, version history, and often redundancy so a single failed disk loses nothing. That redundancy protects against a disk dying and nothing else — a deletion still propagates and it is still in the same building.
5. Judge cloud storage the same way.It covers the building, because it is somewhere else, and most services keep deleted items and versions for a window of around thirty days, which softens deletion and ransomware. What it does not cover is losing the account, or a service closing or changing terms.
6. Separate sync from backup deliberately.Sync keeps a folder identical everywhere, which means it faithfully copies your mistakes: delete a file and it goes everywhere, encrypt it and the encrypted version propagates. It protects against losing the device, not against losing the file.
7. Build the combination that covers every row.Working copy, plus an external drive that is not permanently connected, plus an off-site copy. For most households that is a drive in a drawer and a cloud service, and it takes an afternoon to set up once.
8. Choose the drive type for the job.Solid-state drives are fast and rugged for a drive that travels, but they are not the better choice for a copy left unpowered for a long time. A conventional hard drive is cheaper per gigabyte and well suited to a backup that sits in a drawer.
9. Think about who else needs to reach the files.If two people need the same photo library from different devices, a network drive or a cloud service is the practical answer and an external drive is not. Household use patterns often decide this more than any technical argument.
10. Test a restore, then diarise it.Restore one real file and open it. An untested backup is an assumption. Once a year is enough, and it is the step that separates a backup from a folder you copy things into.

Tips

• Keep the external drive somewhere other than beside the computer if you can — a relative's house, or at work. It converts a home backup into an off-site one for nothing.
• Encrypt any drive that leaves the house, and store its recovery key separately. A lost unencrypted backup drive is a data breach in a drawer.
• Drives are consumables. Replace a backup drive every few years rather than waiting for it to fail, and never let the only copy of anything live on a single external drive.

Common mistakes

• Treating cloud sync as the backup — Sync copies the damage. Deletion, overwriting and ransomware all propagate to every synced copy, usually within seconds.
• Leaving the backup drive permanently plugged in — It is then just another connected drive, exposed to exactly the same ransomware and deletion events as the internal one. Unplugging it is what makes it a backup.
• Relying on a network drive's redundancy as a backup — Redundancy protects against a disk dying. It does nothing about deletion, ransomware, fire or theft, all of which take the whole unit.

If it doesn't work

Questions people ask