Walkman ("walker" in English) is a trademark for a portable cassette player that was listened to with headphones. It was invented by the Sony company in 1979 at the request of one of its founders, Masura Ibuka, although there was an earlier model patented a few years earlier called Stereobelt ("belt with stereo") that its inventor Andreas Pavel did not commercialize, but that maintained a lawsuit with Sony for the recognition that lasted 25 years.
