External hard disk: external storage space

NAS: A Synology NAS (Network Attached Storage) is actually not what the name stands for. It is actually a small server with all the associated functions. A NAS with 2+ hard disks also offers the possibility of a RAID network, which massively increases data security.
For example, you can set up a backup internally on the NAS, which backs up the desired folders according to a schedule. If you accidentally delete something, you can retrieve it without any problems. The data could also be encrypted and access restricted to certain users. This is only a small selection of the possibilities.
Simply put: A NAS offers various functions around data security and management, which a simple external hard drive lacks.

A NAS offers, among other things, the possibility to store one's data redundantly and thus prevent data loss due to a defective hard disk.