Throughout this book's first 12 chapters, you have seen how the conversion to digital is changing the process of video production. In most cases, however, these changes have been evolutionary. Digital cameras, video servers, and nonlinear editors, for example, are certainly great innovations, but they do not fundamentally change how video professionals work or how the viewer ultimately sees the finished program. More often than not, the new digital technologies merely provide video professionals with faster or higher-quality ways of doing the things video professionals have always done.

But the rise of digital is also offering entirely new ways of distributing video and audio information, regardless of whether the production is undertaken in a studio, in the field, or with a remote truck. For its first half-century, video was viewed exclusively on television sets_the signals distributed through the air, over a wire, or on a videotape to the viewer's home. Now, as video technology continues to merge with computer technology, we can watch television on our computer screens and use media such as optical discs to record and play back video on both our computers and our televisions. Perhaps even more significant, the Internet can be used to make video available any time a viewer wants it. Would you like to watch a story from yesterday's evening newscast? No problem if the video is available on the station's website.

These new delivery systems hold the potential to fundamentally change how viewers watch television, and even change what "television" means. Their inherent interactivity, or ability to be actively controlled by viewers, adds another dimension to video production. Where productions for traditional television normally have a set beginning, middle, and end, for example, interactive productions might play differently for different people. Perhaps your story could end either with the boy getting the girl or with the boy losing the girl_depending on what the viewer wants.

The disciplines of using these new delivery systems include the fundamental concepts already discussed throughout this book. Aesthetically good shot framing, quality sound pickup, coherent graphic design, and logical editing, for example, are as important in interactive delivery methods as they are on traditional television. The availability of impressive "bells and whistles" does not lessen the need for discipline in using them. The techniques of using these new delivery systems include a basic understanding of how they work, as well as how video and other information must be prepared for them.

It is beyond the scope of this chapter to discuss all types of interactive systems, especially advanced ones like video games and virtual reality simulators. It is also beyond the scope of this chapter to address in detail all aspects of interactive systems such as Web-page authoring and the use of text, graphics, and multimedia elements. Instead, this chapter concentrates on making video and audio available on nonlinear media, namely the Internet and computer optical discs, as it presents the following topics:

• Basic principles of interactivity and dynamic content, and how they affect video and other information delivered via the Internet and computer disk (13.1)
• How links, screens, and menus are used to deliver interactive content (13.1)
• Basic principles of using video on the Internet, including streaming technology (13.2)
• How Web pages are created to provide access to Internet-based video and audio information (13.2)
• Basic techniques for recording video onto computer-based optical discs (13.3)