WD My Book - External Hard-Drive External harddrive You can also choose from

You can also choose from several fun clock face designs

Automatic software updates keep your system up-to-date and secure

or to charge your device with the included power adapter

Corded/Cordless Cordless

Measure calories burned

WD My Book - External Hard-Drive External harddrive You can also choose fromWD My Book. Compact outside. Powerful inside. Store massive amounts of photos, videos, music and documents with My Book desktop storage. Complete Backup. Equipped with WD Backup software for Windows and Apple Time Machine compatibility for Mac, the My Book desktop hard drive can back up your photos, videos, music and documents. The My Book desktop hard drive also works great with Acronis True Image WD Edition software to schedule full system backups.