Nowadays, there are many different concepts for data protection. The simplest, but probably also the most time-consuming, is the backup of your own data to a DVD-R medium. In the long run, however, this type of data backup becomes very time-consuming and costly.
It is therefore far more sensible to back up your own files on a hard disk. For this purpose, the Raid 1 procedure is suitable. With it, two hard disks can be mirrored 1:1. If one of the two hard disks now gives up the ghost, then all data is still on the second hard disk. For the Raid 1 procedure, however, you need two SATA plates of the same size (from 50 €) and a Raid 1 controller (from 20 €). These must then be professionally installed in the PC and the old hard drive copied into the new Raid 1 system.
For all those for whom this is too complicated, there is a much simpler variant. With some free tools, it is possible to copy important data to an external hard drive, thus protecting it from hard drive damage or accidental deletion.