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What is the difference between backup and sync?

What is the difference between backup and sync?

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Data backup and data sync are different approaches to storing and updating files that have become popular with the rise of cloud storage(new window). Knowing which one to use and when is one part of using your cloud storage effectively.

The short version is that a backup is a copy of a file that you store so you can retrieve it if you need it, while sync involves having a file in two or more locations where changes made in one copy are reflected across all others. Because of this, they have very different uses.

What is data backup?
What is data sync?
When to use sync vs. backup?

What is data backup?

The idea behind data backup is simple — you make a copy of an important file on your computer or mobile device and store it where it’s secure and accessible. You still have the original copy, but the new one is somewhere safe, either on another device, an external hard drive, or — best of all — sitting in a secure cloud storage account.

There are a few reasons to do this, but the main one is to protect your files or a version of your files. A good example is if you created a video or wrote a text document and you want to preserve the original version in case something goes wrong while editing.

Another important reason to create a backup is to protect files in case something goes wrong with the device they’re on. For example, you likely want to back up your photos in case your phone is stolen, broken, or lost. When that happens, your pictures are likely gone with the phone unless you have backups.

Finally, backup is just another word for storage: Once you’ve created a copy and sent it to your cloud storage you can delete the original to free up space on your laptop, smartphone, or other device. Though you likely shouldn’t do this with files you need daily, you can easily archive older projects (school reports, work presentations, etc.) in this way.

In most cases, you can handle backups yourself. Whenever you have something that’s too important to risk losing, just manually copy that file and move it to your storage of choice. Of course, it’s better to do so at set intervals ⸺ we recommend monthly ⸺ and some specific software can even schedule backups for you. 

What is data sync?

Data sync is different. While backups work at set intervals and create copies, sync — short for synchronization — replicates the same version of a file across multiple devices. Any changes made to a file on one device propagate almost instantly across all other versions on all other devices.

For example, if you use Proton Drive, you can create synced folders on your hard drive using our Windows app. Once you put a file into one of these folders, a new synced version of that file will appear in the cloud and the Proton Drive app on your other devices (if you’ve installed it). When you make changes to that file, like adding some text to a document or manipulating an image, the new version will overwrite the old version across all those devices.

This is a great way to keep all your files up to date, especially for people who work on multiple devices. You can shoot a picture on your phone, edit it on your laptop, and view the final product on your tablet without having to copy anything or transfer any files. 

Sync also makes it easy to collaborate with several people, whether at your job, university, or school. If you set the sync up correctly, you can work on a single document with a group of people and, as long as everybody is connected to the internet, you can easily track each others’ changes. 

The only downside is that sync can take up your storage space if you’re not careful. If you edit an image or video so that its size increases, it will take up more space on all the synced devices. This could potentially be an issue if you have limited space on your hard drives.

When to use sync vs. backup?

Though data backup and data sync may seem similar at first glance, they have different uses. You should back up files if you want to preserve a specific version of that file, either because you don’t want to lose it or to make sure you have the original version before you start editing.

For backup purposes, sync is almost completely useless: Synced files update themselves every time a change is made, making them no good for preserving specific versions of files. Sync is what you need when you want to have changes reflected across multiple file instances in real time or when you want to work with the most up-to-date version of a file. 

If you’re thinking like an archivist and want to ensure nothing happens to a file, you want to back it up. If you’re collaborating with several other people or working across multiple devices (or both), you want to sync your files. 

Proton Drive can do both, offering static storage for backup as well as sync. You can even switch sync on and off(new window) for specific files, meaning you decide how much space your synced folders take up. The result is a cloud storage service that lets you switch between sync and backup on the fly.

However, the biggest advantage to using Proton Drive is improved security and privacy. Unlike most providers, Proton was founded with privacy in mind first and foremost. All your files are stored with end-to-end encryption(new window), meaning we can’t see the contents or most of the metadata of your files even if we wanted to. Unlike Google Drive, our business model is based on protecting your privacy, not exploiting your data for profit.

If you’re interested in backup, sync, and taking back control of your data, Proton Drive offers 1 GB of storage for free. By signing up, you’ll be supporting our mission to make the internet safer and more private for all.

Keep your files private, share them securely
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Fergus O'Sullivan(new window)

Fergus has been a writer, journalist, and privacy advocate for close to a decade. In that time he has run investigations of the privacy industry, written on policy, and reviewed more programs and apps than you can shake a stick at. Before starting work at Proton, he worked for publications such as How-to Geek and Cloudwards, as well as helping host events at conferences like RightsCon.

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