An ASUSTOR NAS or network attached storage is a computer appliance built from the ground up for storing and serving files. It attaches directly to a network, allowing those on the network to access and share files from a central location. With the advent of cloud computing, a NAS can be thought of as a type of private cloud storage service. Once you have a NAS, you can centralize all the data you have scattered across all your devices and can access it at any time.