How Much Does RAID Cost?
A RAID (Redundant Array of Inexpensive Disks) is basically a way to add extra hard disks in order to obtain resilience, speed, or both. Probably the most common configuration in a desktop machine (as opposed to a server) is RAID level 1, also called “disk mirroring”. You basically just add in an extra hard disk and arrange for some software or hardware to take care of writing everything you do to two disks instead of one. If one of the disks dies, then you can keep right on working (hopefully with a nice error message to tell you that you should get one of your drives replaced at earliest convenience).
