These are some of the tools I use or have used myself, not only for backing up but set-up, so they run automatically without me needing to remember to do anything.
Use Your Existing Cloud Services, iCloud, Google One, OneDrive
Although it can be debated whether cloud syncing services are proper backup, they are in many cases better than nothing.
One significant exception for these are that they come built into devices (Apple, Android and Windows, respectively) and have backup features built-in, so they are designed for actual backup as well as file syncing.
You can restore or set up a new device with your data using these services. If you have them available, you should enable them and take advantage of the features.
Since these are online services, one caveat is how much storage you get. You may have to pay for higher tiers of space depending on how much you need to back up.
The convenience is that these also have family options to organise all your household devices.
Use Your Built in Backup Apps, Time Machine, Windows Backup
These are for laptop and desktop devices, respectively, for Mac and Windows.
Like some of the cloud services above, these are built-in, but these are used more for local backup than cloud backup.
They are very convenient in storing file history, so it’s worth having these running in the background when you want to revert to older versions of files.
They also work with external drives, so you don’t need to take up space on your machines while also separating your backup from your device (e.g. with hard drive failure).
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