Backing Up Your Mac —
Keep It Safe, and No,
Time Machine is NOT Enough
I’ve added and reorganized some pages on backup and data safety to the main index page. I’ll be expanding this area in the future.
I recommend no fewer than three (3) external backup drives, stored safely away from your computer so that the backups are not subject to the same risks as the computer (theft, fire, tsunami, lightning strike, dog, dinosaur, rats, children, etc). Although with a few of those, your data might be a distant secondary concern.