BY MARY BETH ROCHE

Where do you listen—at the gym, in the car, at work, in the garden? However you answer that question will most likely influence which format you choose. While technology for the printed word has remained relatively stable, change has been a constant for the spoken word since Thomas Edison recorded and played "Mary Had Little Lamb" on a tinfoil cylinder phonograph in 1877. The earliest form of the modern commercial audiobook was a durable long-playing record called the Talking Book, which was created in 1932 by engineers working for the American Foundation for the Blind. Open-reel audiotapes hit the consumer market in the 1950s, and then in the 1970s audio cassette players became standard equipment in cars and Sony introduced the Walkman. For the next 30 years the cassette remained the dominant format for audiobooks. Now the more than 23 million Americans who enjoy audiobooks while they are driving, exercising, gardening—whenever their eyes are busy but their brains are free to learn or be entertained—listen to a wide range of formats, from the still-present cassette to CDs, MP3 CDs, memory cards and self-playing digital audiobooks, as well as downloads on iPods and other digital music players, mobile phones, personal organizers and even GPS receivers.

Since most people listen to audiobooks in their cars, the factory-installed hardware in automobiles is still the greatest influence on format choice. While CD players have been installed in cars for years, it is only recently that CD players have been in the majority of cars on the road, causing the popularity of CDs as a format for audiobooks to rise dramatically from 35 percent of industry revenue in 2002 to 63 percent in 2004. Not surprisingly, cassettes have had a precipitous drop from 58 percent of sales in 2002 to 30 percent in 2004.

As cassettes decline, one format that is experiencing explosive growth is downloadable audio. What's more, interest in the format and technology is actually bringing new listeners to the audiobook experience. Audible.com, a leading provider of downloaded audiobooks, has reported that 50 percent of their first-time customers have never listened to an audiobook before. And libraries are getting into downloading, too. Many libraries are offering patrons the option of downloading directly from the library web site and others offer pre-loaded digital players for borrowing.

Technology is changing so quickly that it is hard to predict what formats audiophiles will be using in the future. Certainly the rise of downloading and the decline of cassettes will continue. But if the glacial decline of cassettes is any indicator, the CD will have a fairly long shelf life. As the cost of memory cards decrease, other tangible formats using that technology should become more popular. And each year more new cars are released with docking stations for digital players or even wireless technology built into the dashboard. Already consumers who love their new gadgets and want to use them on the road without investing in a new automobile have access to numerous affordable adapters that will work through their current car stereo or radio. The technology committee for the Audio Publishers Association has been working with the Consumer Electronics Association to ensure that the next generation of players will accommodate the particular needs of audiobook listeners.

While we all pay attention to trends in formats, in the end, no matter what method you choose for listening, it is still the author's words and the narrator's skill for presenting them that keep you coming back for more.

Mary Beth Roche is president of the Audio Publishers Association and publisher of Audio Renaissance, the audio division of Holtzbrinck Publishers, LLC.