Having lost data due to faulty backup systems, I can attest that a quality backup program is critical. Contrary to the thinking of a decade ago, tape backups or CD backups don't hack it.
Ideally, one should store the back up media in safe place far away from the original data source. If you back up to an external hard drive and their is a fire or flood, you will lose both the computer and hard drive.
Interestingly, the Internet and broadband communications have opened a new backup market. Rather than storing back ups on questionable media. Online services allow people to store backups in remote secure data centers. These centers store your backed up files on media that is far more secure than what you use at home.
This page lists web sites offering automated backup procedures or sites offering remote diskspace.
BTW: After loading a back up program, you need to make sure that you can restore from the program.