Definitely File History on Windows + Track Changes in Word.
(Or on macOS, using a file system which supports Browse Versions and enabling Time Machine backups as well.)
For things you really care about, periodic cloud backups and/or cloud saves as well, and periodic print copies for good measure.
The saddest thing is when someone's laptop with all of their data or documents is stolen, or their data/documents are destroyed physically in some disaster, and they have no backup.
(Or on macOS, using a file system which supports Browse Versions and enabling Time Machine backups as well.)
For things you really care about, periodic cloud backups and/or cloud saves as well, and periodic print copies for good measure.
The saddest thing is when someone's laptop with all of their data or documents is stolen, or their data/documents are destroyed physically in some disaster, and they have no backup.