TidBITS:

I humbly submit that Friday the 13th, whenever it rolls around, should be considered International Verify Your Backups Day. (The United Nations is welcome to make this official.) In 2017, we’ll be celebrating in January and October. If you’re reading this article on some other day, I’d encourage you to verify your backups right away and then continue with the Friday the 13th schedule.

Take a few minutes to identify some critical files and see if you can restore them successfully from your backups. If a bootable backup is part of your backup strategy, make sure you can actually boot from it.

That’s it. No costumes are necessary, there’s no obligatory greeting, and you aren’t expected to make a special meal.

This is just as fake as any of the made up “International Day of…” you see on Twitter but this one actually has a great message – your backups are useless if they can’t be used to restore your data.