Network Attached Storage units let PCs share data - USATODAY.com

They look like hard drives, but they act unlike any hard drives you've ever seen. In the industry, they're referred to as Network Attached Storage (NAS) units. But I'd call them Digital Media Control Centers.

They're hard drives that plug into your network router to push music, video and photos to the computers in your home or office. They also can back up your data, stream music from your iTunes program and make the data available remotely...