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Just What Is a Backup, Anyway?

Backing up is incredibly important, and it’s something I harp on a lot.

It also confuses a lot of people with its esoteric terminology and concepts.

In this article, I’m going to tackle the most fundamental term of all: “backup”.

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Backup basics

A backup is something very simple: it’s a copy — a copy of a file, of your data, of a computer, of an operating system, of anything or everything.

Remember this phrase:

If there’s only one copy, it’s not backed up.

By that, I mean if you have only one of something — call it the original if you like — and something happens to it, it’s gone forever. If a hardware failure, malware, account hack, or similar scenario takes away that one and only copy, it’s gone.


That’s why I harp so much on backing up.

And backing up is nothing more than making a copy of something.

Backup locations

Backup Flash Drive Almost as important as making a backup is where you put it.

When we back up, we make a copy somewhere else. Now, “somewhere else” is open to interpretation, depending on what you’re doing, but the important thing is that if you make a copy of something, you’re backed up, and the further away that copy is from the original, the more protected that copy is, and the safer that copy is.

For example, if you’re working on a word processing document, you might:

  • Click on Save to copy what you’re working on to disk.1


  • Click on Save As, and save the file with another name; this will copy what you’re working on to disk, without overwriting what you started with.

Those types of actions are going to protect against certain types of failures that would otherwise lose your work. For example, they might protect you from application crashes, changes you make by mistake, or perhaps even accidentally deleting the file.

They’re not, however, going to protect you from things like hard disk failure or malware. Moving your backup further away from the original location protects you from more and more things.

  • Storing on an external drive might protect you from a variety of hardware and software failures on your computer.
  • Storing on an external drive you then disconnect and keep in your desk drawer would protect you from all that, plus malware that might attempt to harm data on external drives (such as some variants of ransomware).
  • And, of course, storing it online, or on a disk in a bank vault, would protect you from all that and more, including your house burning completely to the ground.

Each is conceptually, and often physically, a little “further away” from the previous location.

Back up or backup?

And finally one little clarification:

Is it backup or back up?

This is something that my editor catches in my writing frequently.

Backup is a noun or adjective. A backup is a thing. I have a backup or a backup copy or a backup of my hard disk.

Back up is a verb. To back up is an action. I make a backup (thing) by backing up (action).

So a backup is the thing you’re trying to create, and backing up is what I’m encouraging you to do.

Do this

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Footnotes & references

1: You can often tell how “experienced” a computer user is by how much of a habit they have of pressing the “Save” shortcut, typically CTRL+S, as they work.

2 comments on “Just What Is a Backup, Anyway?”

  1. Good article! Short and concise!
    Don’t forget that the “cloud” is an option for backups as well.
    I have my data backed up that way nightly and it’s comforting to know that I have an off-site backup of my data, current, in case I should need it.


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