The answer is simple – for two reasons:

• To restore the last (backed up) state e.g. after a hardware or software failure.
• To retrieve old versions of a file or folder because the data was deleted or destroyed without being noticed (e.g. due to a software error). Or to only notice later that the file(s) were accidentally deleted.

The most important backup is the one you didn’t make!

The amount of your personal data increases significantly over the years. As already described at the introduction, this is all data, such as for example family pictures, documents, e-mails, etc.

All data is stored on your computer – more precisely, on your hard disk. This storage medium holds your data and on it you can store, retrieve and edit other data. Modern technology is very advanced and durable, but not immortal. 

The technical equipment, such as the hard disk, lives a certain number of operating hours. Depending on use and stress, this can be longer or shorter. At some point, however, malfunctions and defects will consequently occur due to wear and tear. In exceptional cases, even a new hard disk (in principle, this applies to any storage device) can become defective. The consequences are that your computer cannot be started, you no longer have access to your data and, in the worst case, the data is lost due to a defect. It can also be caused by malware, such as a computer virus or ransomware preventing you from accessing your data or intentionally deleting it. 

Therefore, it is very important that your data is at least duplicated and independent on different storage media. This means that you do not store any backup on the same hard drive, because the data backup itself can also be lost due to a defect. Here, physical separation is very important – that is, an extra storage medium, such as a separate hard disk.

You need to decide how often you should perform a data backup. It depends on the frequency, how often you change your data. With a manual backup, it also requires a certain discipline to perform it regularly yourself or have it performed by backup programs