Excellent advice. Fortunately the price of storage has dropped so much over the past couple decades that having everything you need to backup your computer quickly and easily is very low cost. To be exact:

• $55-110 dollars for a easy-to-use USB external hard drive with 1-4 TB of storage

For fellow readers who use MacOS you'll find the backup software is built-in and super-simple.

Just go to: System Preferences and select Time Machine. Switch it "ON" and select your preferred disk for storage. I use a Western Digital My Passport USB drive.

After that the only thing you need to do is periodically connect your USB drive and Time Machine will automatically backup any recent changes to your MacOS device. It will also remind you if too much time passes without a backup.

For users of Windows 8 or later File History is the tool you'll want to find. I also recommend creating a complete system image which gives you a complete snapshot of your system on the date you create it.

Later you can restore the image so that even if you experience complete data loss or hard drive failure you can simply replace the failed drive, restore the image and you have your baseline system back.

In other words: Create a system image as a baseline and use File History (for Windows) or Time Machine (for MacOS) to keep up with day-to-day, week-to-week changes to your files.