A young man jogging beside the Charles River in Boston. An artist at work in her Los Angeles studio. A truck driver making a coast-to-coast run in a 16-wheel rig. A New York City commuter stuck in his car in rush-hour traffic.
What do such people have in common? While otherwise engaged, they can listen to a book - recorded on cassette tape. Right now, thousands of people like them are discovering a whole new area of enjoyment, that of hearing books read aloud.
Books on cassette aren't exactly new, but their popularity is definitely on the upswing. High school teachers discovered years ago that a cassette of a well-dramatized story - say an Edgar Allan Poe tale - may be the key to getting a whole English class excited about literature.
In a few cities and towns and on several college campuses, libraries have been building tape collections, which have proven quite popular with adults as well as students. The recordings don't necessarily take the place of reading books and aren't designed for the use of the blind. In fact, they are often enjoyed by the most avid readers, some of whom like to listen when they can't be reading. Old-time radio fans are also among committed listeners.
There are hundreds of books available on tape. Depending on interest and taste, one can find a classic like Charles Dicken's ''A Christmas Carol,'' a current title like ''The Art of Japanese Management,'' a book from the New Testament, a Shakespeare play, a biography of Eleanor Roosevelt, or a gripping mystery. Poetry fans can listen to Robert Penn Warren reading his own works.
Although the audio-cassette tape made its appearance in the mid-1960s, books weren't recorded in earnest till the '70s. Now an estimated 60 percent of Americans have cassette players in their cars, and 75 million to 80 million have them in their homes, according to one books on cassette company owner. These numbers, together with the recent boom in compact, portable players with earphones, suggest to some tapemakers that the market is just beginning. There are no known figures for the numbers of companies. But a number of firms, many of them small operations that aren't even listed in the Yellow Pages, have plunged into production.
One of the oldest firms, The Mind's Eye, in San Francisco, started 10 years ago. The company originally produced dramatized adaptations of books primarily for schools. Its founder, Bob Lewis, who has a PhD in English literature, selected the books and adapted them into scripts. He's still selecting and writing, although the company has grown considerably.
In a telephone interview, Dr. Lewis explained that the listening audience has changed over the decade from an academic to a more general one. The Mind's Eye is now choosing books to appeal to commuters, postal workers (who are allowed to listen on the job), homemakers, students, and especially to families that may be looking for a new kind of entertainment for car trips. The Mind's Eye features dramatized recordings of abridged works, and its products are being marketed in bookstores this fall for the first time.
Recorded Books, in Clinton, Md., has a different story to tell. Sales manager Sandy Spencer says his company specializes in unabridged recordings of books. Recorded Books lists over 150 titles in its catalog, varying from classics to best sellers. The company was started by a traveling salesman, Henry Trenton, who wanted to do more reading but couldn't. He called up a California distributor to order tapes of a book to listen to on the road. Soon he and a friend launched their own recording and distribution company.
Recorded Books uses a single reader for an entire text - usually an experienced actor, who, rather than dramatizing the work, simply strives to suggest the characters and to become the author's voice, speaking directly to the listener. Some listeners prefer this style of recording to a dramatic rendering.
Recorded Books not only sells but rents out its cassettes. Rental offers significant savings. For example, the seven-cassette package of Judith Guest's novel ''Second Heaven'' sells for $67.35. To rent the set for 30 days costs $11. 20. Recorded Books has a toll-free telephone number for handling orders and can deliver within seven days.
A forerunner in the recorded-books field is Caedmon, which for many years produced the finest-quality spoken LPs available, featuring every subject from plays, poetry, and essays to speeches and letters. Caedmon has quite naturally moved into cassettes in a big way. One of its catalogs, the Spoken-Word Classic series, contains over 300 titles. The current catalog of new recordings, which also contains a backlist of best sellers, includes an extensive list of children's books. These recordings range from one individual reading to a full cast.
Caedmon recordings are available only for sale; there is no rental program. They are available in many book and record stores. The company features attractive offerings for libraries, so their tapes are also available there in some areas.
Books on Tape, in Newport Beach, Calif., started in 1974 and now offers over 800 full-length recordings of popular best sellers. For example, it offers Robert Ludlam's international-intrigue thriller ''The Parsifal Mosaic,'' which takes 27 hours to play. This set of tapes comes in two parts, nine tapes each, renting for $4.50 a part.
Books on Tape offerings are mostly recorded by a single reader. Selections in the catalog include not only books but seminars on business and other subjects, foreign language training, self-improvement - even auto-travel tapes keyed to US National Parks. With such a varied selection, it's not surprising that the company has some 25,000 customers.
Now 27 hours of one book may sound like too much. However, for a postal worker who doesn't have to apply full concentration to routine tasks, it may be only a week's involvement. A two-hour-per-day commuter could be occupied for two weeks. But the problem is, once one gets into a book it's very hard to put it down, or, in this case, turn it off.