As Jay mentioned in Why you shouldn’t delete your Facebook data — even if you delete it many Facebook users have decided that it is time to delete their accounts. Several Backupify users have asked, “What exactly do you backup?” That’s an important question.
We backup your uploaded photos, photos of you that have been tagged, your friends list, statuses, links, notes, and events. Photos are only available in Facebook’s downsized resolution and all other data is in an xml file.
While backups work correctly in most cases, it is important that you check your backup archives before doing anything drastic. For certain accounts, especially large ones, we have noticed inconsistencies in the data that the API returns.
Occasionally we see a message such as, “this API call could not be completed due to resource limits.“ This limitation may result in an incomplete download of statuses, friends, and other information. We can only backup what the API returns. If you’re planning on deleting your account, proceed with caution.