Network-attached storage (NAS) is file-level computer data storage server connected to a computer network providing data access to a client computer or group of clients. NAS not only operates as a file server, but is specialized for this task either by its hardware, software, or configuration of those elements. NAS is often manufactured as a computer appliance – a specialized computer built from the ground up for storing and serving files – rather than simply a general purpose computer being used for the role.
NAS boxes are manufactured by Seagate, Netgear, Synology and numberous other manufactures. Prices range from about $140 to $100,000. Using a NAS and a program like FreeFileSync is a perfect system for backing up all of files on all of your computers.