NAS is a new term for something that’s been around for quite a while: clients
accessing the storage attached to a server. For example, UNIX clients that use
NFS to access files on a server, or Microsoft Windows systems that use CIFS
to access files on a Windows server. Many vendors package turnkey network
file servers that work out of the box with several file-sharing protocols.
Network Appliance and EMC make such systems for large storage needs; Linksys and other companies make smaller systems for consumers and small
business.