The My Book-2 Tb is a sleek, compact designed external hard drive unit which will store all of your photos, music, videos & media so with its 2TB capacity it provides you with enough space to hold on to your families digital life. With the Western Digital smartware backup software you can back up all your files & data easily & it will do this quietly in the background, so whenever you save, add or change a file it will back it up, making you safe in the knowledge that your precious memories & important files are safe. & with the security function it means that you can set a password & encryption for your drive to protect your files from intrusive use or access. The Mybook 2TB is compatible with USB (Universal Serial Bus) 2.0 & also USB (Universal Serial Bus) 3.0 for when you want that faster transfer rate which can be up to 3x faster compare to the USB (Universal Serial Bus) 2.0.