DVD stands for digital versatile disc. Originally the initials stood for digital video disc, but because the DVD disc and its underlying technology are coming to be used for many purposes in addition to movie and video presentations, digital versatile disc is becoming its more common meaning. With its superior capabilities and its inherent economies and efficiencies, the DVD will, in large measure, soon replace videotape, laserdiscs, music CDs, CD-ROMs, and, eventually, books on paper. "How Tomorrow's Movies Will Differ" describes why and how books and movies will meld through the use of high capacity media like the DVD.

The DVD technology is one of the mudoc technology's enabling technologies. The DVD technology makes the use of mudoc reference substructures feasible and affordable. By greatly increasing the storage capacity of the compact disc, the DVD technology will make it possible for the reader of mudocs to have easy and immediate access to a very large reference library on a single CD. With such reference materials at hand, the mudoc reader will be able to function as an expert in the language being used in any particular mudoc. With reference substructures and interactive movable type, the mudoc reader will experience a kind of empowerment and fulfillment that no reader has known before.

The maximum storage capacity of a compact disc used as a CD-ROM is 682 megabytes. The DVD technology permits 4,700 megabytes to be stored on that same single-layered CD. And the DVD technology also allows publishers to add up to three additional layers to the CD, increasing the maximum capacity of a DVD to 17,000 megabytes (that is, 17 gigabytes) - 25 times the capacity of a CD-ROM disc. The Encyclopaedia Britannica is now published on one CD-ROM (which includes all 32 volumes, including 4,000 pictorial images and 1,200 interactive maps, plus the last four Britannica Yearbooks), so one DVD can hold the equivalent of 25 such collections of information. (The multimedia edition of the Encyclopaedia Britannica requires two CD-ROM discs, so the equivalent of a dozen such "multimediapedias" could be published on one DVD.)

The cost of "printing" mudoc reference substructures on DVDs will be far less than printing the same documents on paper. Once the hundreds of thousands of pages of reference materials have been placed on a DVD master, that master can be duplicated on additional DVD discs for a few dollars each. The cost of printing the same information on paper would be hundreds of dollars. Other advantages reference libraries on DVDs will have over reference libraries on paper: (1) faster and easier access to the information, (2) much lower transportation costs, (3) much smaller storage requirements, (4) much easier updatability, (5) the fact that the text in the mudoc reference substructures will have been set in interactive movable type, and (6) the fact that DVDs don't require the raping of forests.

One reason DVD players will rapidly supplant CD and CD-ROM players is that DVD players can play CDs and CD-ROMs as well as DVDs. DVD drives presently cost about twice as much as CD-ROM drives, but, much like their cousins, the personal computers, DVD drives are continually offering greater and greater capabilities to the user for less and less money. DVD drive use is likely to grow rapidly after mudoc reference substructures come into use. Most mudoc consumers will use at least two DVD drives, one for a reference substructure and one for mudocs and other presentations issued on DVDs. If, as expected, mudocs and reference substructures come into wide use, so will DVD discs and drives and their successors. And the companies that are the leaders in the production of DVD drives and discs could experience great growth.

The DVD technology, in combination with interactive movable type and the telereader terminal, will greatly increase each individual's ability to consume information while, at the same time, reducing the costs of such consumption to a point where everyone can participate in the process. And in every nation most individuals will become participants.