The original acronym stood for "digital video disc". However, many of the members of the DVD Forum felt the medium went beyond just video, but the alternative suggestion "versatile" has never been official. In 1999 the DVD Forum decreed that DVD, as an international standard, is simply three letters. See
DVD FAQ.
The Microsoft Manual of Style (for Technical Publications) states that DVD stands for "digital video disc and expressly forbids spelling out the acronym as "digital versatile disc".