Computers are far from perfect, and as a result, they will eventually fail. When they do, all the data that was kept on that system will be gone. And if there weren't any backups, it may be gone for good.
Data Backup is something that is so crucial, yet many companies still neglect to have a complete backup solution, leading to chaos when they find they've just lost the database containing all of their customer data. Fortunately, there are a number of options when it comes to data backup, the two most common being RAID duplicity and external copy.
In a RAID array, there are a number of types (RAID 0, RAID 1, RAID 5, RAID 10), however, not all of them provide duplicity. The most basic array that provides this is RAID 1, where the array is composed of two disks. As data is written to the array, it is written to both disks simultaneously, so that each disk is a mirror image of the other. As a result, when one fails, the data is safe on the other disk until the dead disk is replaced. With this model, the data always has an on site backup.
But what if there were a fire, or some event that resulted in the destruction of both disks on site? Or you needed to roll back your systems to an earlier point in time? RAID duplicity wouldn't be much help then.
For this reason, it is also highly advisable to store data offsite in an external backup. In this model, "snapshots" are regularly taken of the system's state and archived away on a fileserver elsewhere. As long as these backups exist, you can restore parts, or even all, of your system to an earlier version.
RDA have set up many comprehensive backup solutions and can protect your data as well!