For more than half a century, television has been a passive medium. Viewers are rarely encouraged to do more than watch. Occasionally you could make a pledge during a telethon, clap for Tinker Bell, or call a hotline if a neighbor looked like a wanted felon, but television has largely been a simple, one-way stream of information. Now, because of changes in technology, the state of television in America is changing.

Suppose you are watching a documentary film called Partners of the Heart. The film tells the story of Vivien Thomas and Alfred Blalock, a black laboratory technician and a white physician. Together, in the Deep South of the Great Depression, they pioneered heart surgery, which did not exist in a credible form before their experiments. One scene depicts a critical moment in their careers which took place in the early 1960s. Blalock is honored for his achievements in the ballroom of a fancy Baltimore hotel. Thomas, the man who worked at his side for several decades, is watching from the kitchen door; because of segregation, he is not allowed to attend the ceremony.

The same night that Blalock is honored, student demonstrations over civil rights take place in Nashville, the place the two physicians met and first worked together. The juxtaposition of events is interesting, but the storyline jumps back to Blalock and Thomas. Perhaps you would rather follow up on the sit-ins. You choose an icon on your television screen and watch an interview with one of the demonstrators, who is talking about civil rights during the last forty years. Then you switch back to the main broadcast. Later you visit the film's website and study a taxonomy of minority achievers in the medical sciences. You watch a few video clips of these men and women, and decide to contact one of them with the address provided. Maybe you try your hand at heart surgery, using virtual medical instruments. Or you listen to the testimonies of little known, pre-civil rights era Southerners who dared, as William Faulkner once urged, to "speak out against the day."

Not your normal television experience? It will be. This is an example of enhanced television, which uses various digital platforms as its medium. The National Endowment for the Humanities is currently in partnership with the Corporation of Public Broadcasting to fund digital television prototypes such as Partners of the Heart. The idea is to generate parallel production of both multimedia components and the film itself. As project director Andrea Kalin explains, "Instead of going after an interview for a soundbite, I go in with the enhancement in mind." Creating the extra video and audio clips, interviews, and interactive elements while crafting the film "really is a dramatic departure for storytelling, to be able to, at a very deep level, explore three stories on three different trajectories," Kalin says, referring to the personal histories of the two men, the medical drama of a new field, and the backdrop of the social and cultural changes in the U.S. from the thirties to the sixties. "They were looking ahead where there was nothing behind," Kalin says, aptly describing the lives of Blalock and Thomas, as well as the role of TV producers in the television revolution that is taking place now.

The invention and development of digital television (DTV) and other digital technologies are the cause of this revolution. Television sets were first built to receive analog data, which, like radio frequencies, are vulnerable to weather changes and physical obstructions. Digital broadcasts are more distinct and not subject to the same problems. DTV can also be sent by digital cable and satellite transmissions. Broadcasts are made up of compressed binary data, and can only be processed by digital sets or old sets with a digital "box." Digital refers not just to how it is sent but the way sound and audio are captured and presented. DVD (Digital Versatile Disk) is digital technology; so are websites that air programs in real time. A significant difference between analog and digital formats is aesthetic. A digital TV's picture has higher definition, with sharper, more realistic images and a wide-screen format.

Morning Sun, a documentary on the Cultural Revolution in China, is another NEH/CPB project that will benefit from the aesthetic and technical elements of DTV. According to project director Richard Gordon, the initial aim of the project was to "create a public place for the remembrance, recording, and analysis of a history of the Cultural Revolution." This goal is being pursued by the Long Bow Group, which has made several films about China, including the NEH-supported documentary, The Gate of Heavenly Peace, about the Tiananmen Square student uprising. Taking advantage of the current political situation in China, which has made many materials available, the producers have amassed numerous media samples from that time in China's history. Morning Sun's website may offer as many as fifteen feature films, twenty documentaries, and three hundred hours of music for adventurous downloaders.

As in Partners of the Heart, Morning Sun is being designed to present options to viewers. During the broadcast, if a clip of a comic performance is not enough, watch the whole thing--or skip to historical commentary and learn where the humor sprang from. Immerse yourself further in the broadcast by listening to it in Chinese. On the Internet, browse through propaganda posters of Chairman Mao, follow the geographical progress of the revolution on an interactive map, or watch period Soviet documentaries about the Chinese people and government.

Long Bow Group is also partnered with the Massachusetts Institute of Technology to help students and teachers access primary sources. Together they are developing a website that will allow any noncommercial, educational establishment to download the materials. Though the technology proved a little daunting at first, Richard Gordon appreciates the freedom he has in choosing how to put the project together. Gordon avers that it is "a brave thing the NEH is doing" by funding this and similar projects.

Even for programs not specifically designed for digital broadcast, viewers may have more control over the pace and depth of their viewing. DTV allows two-way data exchanges, a simple effect of which is the ability to stop, rewind, or fast-forward a program while it is being transmitted. A station can also multicast several programs or different versions of the same program, as the compressed data allows much more information to be transmitted at one time. So while a child can watch Barney on one TV set, on a different set tuned to the same station a parent can choose a news show.....or Barney in a different language.

Technology advances are transforming websites too. On a broadband webcast, information is sent at a speed more than three hundred times faster than a 56K modem. Think of the difference, for example, in educational programming. Alongside a videofile of a class, there may be a chatroom link to discuss the lesson with other students, links to webpages to help you research your next paper, and that night's homework, all downloadable with the click of a mouse.

With DTV comes the risk that viewers will be overwhelmed by all the choices and information. "The wealth of material to draw upon makes it easy to have interdisciplinary opportunities, but it also becomes more complicated," says Yanna Brandt, project director for the digital programming accompanying one of the films. The prototype she is developing is Crucible of the Millennium, which will examine events around the world from five hundred years ago and their impact through modern times. Fortunately, like other program producers, she remains a filmmaker at heart. "The thrust of all our materials is to be thought- provoking rather than to inundate with fact," Brandt states.

Though the project is nascent, Brandt envisions games for young adults, tours of museums, and interactive dialogs with scholars. There is a plan to include a virtual exploration of a pyramid in Mexico, over which a Spanish church was built, and which was only recently unearthed. Brandt is also working out ways to bring viewers in contact with each other, to discuss and answer the questions the film will raise.

The digital revolution is a quiet one; many stations are already transmitting digitally. In accordance with Federal Communications Commission regulations, the top four commercial networks were required to provide digital broadcasts by May 1, 1999, with many other stations following suit by the end of the year. All commercial stations are required to begin digital service by May 1, 2002. Noncommercial, educational stations are to follow suit a year later. In theory, all programming will be digital by April 1, 2005, with the death of the analog broadcast coming in America in 2006.

Stations have the right to request two six-month extensions on the deadline. Still, it might be difficult for some public television stations to both meet the broadcast deadline and begin generating enhanced digital content. One obstacle is that programming specifically designed for digital broadcast is still a very new concept for producers.

Another prototype meeting the challenge is Woodrow Wilson and the Birth of the American Century. The film and its digital enhancements are being produced by KCET, a public TV station in Los Angeles in partnership with the American Film Institute (AFI). The goal of the project is to use interactive elements, mainly through the show's website, to bring the early twentieth century to life. "We think it is important to connect with young people today so that they know what was going on a hundred years ago," says project director Mitch Aikin. "There was a big technology boom then; there are a lot of parallels between then and now."

A distinction that Aikin notes between public televison projects and other kinds of film and television projects is the relationship between the content and its delivery. "First and foremost, it is the educational content that drives the production of public television," Aikin states. "We create the elements that will reach the most viewers. Delivering educational content is the number one goal. Deciding what technology is the best to deliver--and that changes every six months--is a curveball to deal with."

Sudden and far-reaching changes in technology have become commonplace. Now that there is the means to reach viewers in new and exciting ways, what exactly is the future of television?

"Nobody has any idea," says Louis Barbash of the product development office at the Corporation for Public Broadcasting. "We're trying to fund as many different approaches as possible. You learn as much from the prototypes that dont work as from the ones that do." The various ways of presenting a program--DVD, terrestrial broadcast, satellite transmission, webcasting--make production more complicated. Producers keep in mind the fact that some viewers don't have the right type of Internet connection, or the right TV set to access enhancements. Another obstacle is price: current digital sets can cost thousands of dollars. Like cars, computers, and cell phones, DTV sets will undoubtedly become sleeker and cheaper in the future; but for now, most are priced as a luxury.

Once the price of admission is paid, though, TV will be a different affair. "The interactivity converts a 'lean back' experience to a 'lean forward' experience," Barbash says, and TV producers are beginning to learn how to exploit this. He compares this point in TV evolution to the transition from silent film to "talkies," or from radio to TV. "The tendency is that new fields are dominated by people who know how to use the technology. It takes a while for creative people to catch up."

Margaret Koval of Goldfarb and Koval productions has worked on Woodrow Wilson and other digital TV programs. When speaking of dealing with the new technology, she is enthusiastic. "The merging together of content and technology offers extraordinary opportunities. You can put in so much information; documentaries are so information rich; they are, theoretically, a perfect genre for enhanced television."

Her production company has recently been selected by the American Film Institute (AFI) to work up a prototype for an enhanced documentary about first-century Romans, which received planning funds from NEH. She emphasizes the discrepancy between what digital TV can provide and what the general viewing public can see: "We will be developing enhanced TV just as people are getting the TV sets to view them." Still, the race is on to provide the programming. Koval observes, "How quickly it is picked up depends on what is done now. The basic (digital program) is documentary film, which is very much in the experimental stage."

Like NEH, AFI has become active in promoting digital TV production. Last year its workshop "Enhanced TV: A Historical and Critical Perspective" was produced in conjunction with a host of its own digital prototypes. Forget Napster, a program on the history of Irish rock music includes music, downloads, and interviews with artists. The broadcast of E!'s Talk Soup mirrored its website with bonus, pop-up information. Expedition 360 followed adventurer Jason Lewis around the world on his singular biking-rowing-skating contraption with maps and journal entries along the way. An interactive children's program, The Eddie Files, included games and quizzes for its young viewers. These and the other prototypes may come to typify digital programming, in that from program to program, no combination of technological elements were repeated; producers were able to pick and choose to suit.

Where will all these prototypes lead? Will the television experience of generation Y be as different as generation X's computer experience was from that of previous Americans? Tom DiGiovanni is the director of enhanced programming at the Public Broadcasting Service. Aware that DTV is in its infancy, he is working on developing implementation strategies. "It's just like the beginning stages of the Internet. No one could have foreseen the huge impact it had." While he could not make predictions about the eventual impact, he described the evolution of television from a producer's point of view. "It will be interactive. It won't just be broadcasters pushing out info . . . . It is a hybrid, a completely new media. What a broadcaster does, what a webmaster does, and what a TV producer does, all of these things are melding."

As much as for the producers, the role of the spectator will certainly be different. When a talk show guest makes you mad enough to shout, there will be other viewers at their computers ready to read your comments. Want to try something new to eat? A cooking program can send recipes to your printer. Follow up on the one part of a documentary that interests you the most. Listen to the news in German, Turkish, or Swahili. Viewers will become part of television broadcasts in ways they never have before.

Chrissa Gerard is a writer in Silver Spring, Maryland.

The projects Partners of the Heart, Morning Sun, Woodrow Wilson and the Birth of the American Century, and Crucible of the Millennium have received planning grants from NEH for parallel digital programming. The initiative is a cooperative effort between NEH and the Corporation for Public Broadcasting.