An NAS is a versatile device, that's why there's a great variety of accessories that makes using your network storage easier. The most important one is an internal hard drive, since most NAS don't include integrated storage space. Do you want to store surveillance images? Connect an IP camera and store your video images on your NAS. Do you not have enough network ports to connect your device? Use a switch to expand the number of Ethernet connectors of your modem or router to be able to connect your network storage. Thanks to the extra accessories, you can adjust an NAS to your own liking.