As a discipline and a technology, DAM is all about the control, flexibility, portability, access, and reporting of digital assets between organizations, customers, partners, and suppliers. (Digital assets are files that have an intrinsic or acquired value over their lifetime.)
DAM is concerned with delivering the right content to the right people, on all devices, mostly in real time, with the ability to track and measure digital asset engagement across an enterprise and its potential global reach.
Technically speaking, a digital asset is more than just the media file. To realize the value of a file (or collection of files), you need to have additional information about that asset. In short, you need metadata.