Backup types explained

Backups are an important part of anyone who uses computers to run their businesses. They help recover from disaster or, more simply, can be used to move your data from an older computer to a newer one. Disaster will strike, that’s inevitable with computers, and hardware does age and sooner or later you’ll have to replace your aging computer with new hardware, so one can see how it’s important to get your technology infrastructure (however small and simple it is) back up on its feet when it goes belly up.

I’m personally surprised by how many freelancers and small businesses are careless about their backups, seeing them just as something that “needs to be done from time to time” and generally wasting time backing their machines up manually instead of scheduling them. I believe it’s time  for a change: the data handled and processed during day-to-day work is important, regardless of how small the business working with it is, and I believe it is my duty to educate my readers about this.

This being a website aimed at the inexperienced users, I’ll try to keep the language as plain as possible. We’ll only be dealing with data backups here, not because partition and system backups aren’t important, but because I feel a small business may not need to care about those two. Specifically, it’s easier for a inexperienced user to just reinstall their operating system and applications than to restore it from an image.

There are three main data backup types: full, differential, and incremental. Let’s see briefly what each of them entail.

Full backups

Full backups are the simplest you can imagine and, as the name suggests, are backups where the original data is copied as is every time the backup is run. Being so simple, they’re very easy to perform and schedule, because you only need to tell the computer what folders and/or files to copy to the new location. This simplicity is also their biggest issue: they’re easy to do, yes, but this also mean they can get really big, really fast. The same data has to be copied multiple times, leading to a waste of drive space.

Differential backups

Hard drive space may have become cheaper in later years, but it hasn’t become completely free. We previously touched this topic on our Computer Buyer’s Guide, which included this graph:

Comparison between the price per gigabyte of Samsung 850 EVO SSDs and WD Blue HDDs. (Click to enlarge)
Comparison between the price per gigabyte of Samsung 850 EVO SSDs and WD Blue HDDs. (Click to enlarge)

All those storage devices will eventually run out of space, and full backups will fill them even more quickly. There must be a way to backup data to preserve space, right?

Actually, there are two. The simplest of which are called incremental backups. The way they work is relatively simple, but effective: instead of backing up everything, they will only create copies of files that have been edited or created since the last full backup.

Incremental backups

Differential backups are a great step up from full ones, but there’s still room for improvement. If your data changes too much since the last full backup, you’ll end up with pretty substantial incremental backups. A better space-saving measure is to just backup what has changed or has been created since the last backup, regardless of its type.

This is what an incremental backup does. Compared to the other two backup types, they’re the least aggressive in terms of disk usage, for they will need to copy just a small amount of data every time.

What backups should you run?

If you’ve paid attention, you may have realized that both differential and incremental backups require at least one initial full backup. This is normal and, to a degree, even obvious. However, they will help you save space as your backups grow larger and larger.

Tech 4 Freelancers will keep covering the topic of backup types in the future, with more guides and tips to help you create a good backup strategy that will keep you safe even in the face of disaster.

About Andrea Luciano Damico 137 Articles
Andrea Luciano Damico is a freelance translator from Italy. Among his interests are linguistics, technology, video games, and generally being a chill guy. He runs Let's and