The Buffalo Technology DriveStation HD-CEU2 is an external HDD that connects to PCs, Apple Macs, LinkStations, and TeraStations via USB 2.0. It can also connect to a wireless router via USB, and then be used as a Network-Attached Storage device. Once plugged into a compatible Windows or MacOS computer, it automatically installs and is immediately ready for use. Included with the unit is SecureLockWare, a 100% free security software that allows a user to encrypt either all or just a part-of the data on their HDD device; and also Memeo AutoBackup & Memo AutoSync, built for securely storing and tracking essential computer files. Note that the DriveStation Combo retails in four forms, ranging from 500GB to 2TB.