the data discman is an device that plays electronic books. it was made by sony corporation, which was the parent company of sony pictures entertainment. it came out in the western market in late 1991 or early 1992. it was marketed in the united states to college students and international travelers, but was only successful in japan. the discman product name was first used for sony's range of portable cd players, such as the sony discman d-50, which first came out in 1984.