Technology called RAID (Redundant Arrays of Inexpensive Disks) can be setup with an additional hard drive to create an exact copy of the hard drive you use. Flash or thumb drives are widely available and have become very inexpensive. External hard drives are also becoming cheaper in price and are intended for backing up entire computers or large amounts of data like music or video. Entire computer backups should be stored on a separate physical drive and should be done weekly or monthly. Online storage options are also available for backup, ranging from limited free versions to monthly plans.”]
Source: https://www.cuinfosecurity.com/data-loss-how-to-help-protect-your-digital-assets-a-778