An important, but quickly forgotten aspect of computer security is backing up important data.
In general there are two types of backups, full and incremental. A full sized backup will have a size in the same order as the original, before compression. An incremental backup will save only the changes since the last backup. By nature these will always be based on a full backup.
Storage is an important factor. How many backups do you need? Will there be circumstances when you need to go back more then one day? Maybe even a week? How often do you make a full backup and how many incremental backups will be made in between?
Another thing to consider is whether the backup device is bootable. In other words, do you need to copy the backup to the original place first or can you boot from the media device?
In case of disaster the data and the backup should be so far apart that the disaster can’t destroy them both. After all if the backup is destroyed in the same fire what good will it do you?
Although some solutions like the ioSafe Solo can withstand a lot. 😀