What is the difference between Deactivating and Deleting an account?

Deactivation is temporary: your profile is hidden, but your data is saved, and you can return anytime by logging back in. Deletion is permanent: after a 30-day grace period, all your photos, posts, and videos are removed from Facebook's servers and cannot be recovered. Note that Messenger remains active if you only deactivate Facebook, but is lost if you delete it.