The Walkman was invented by Sony Corp. and was the device that changed the way we listened to music. With the Walkman, we could listen to music anywhere for the first time.
The first Walkman required 4 AA batteries and came with earphones. It had crystal clear sound equivalent to 1000 Watts or so and the stereophonic effects were simply fantastic. You could feel one sound travelling from one ear to the other!
Most importantly, the batteries lasted for a long time (4-5 hours at a stretch).
The Walkman proved to be a wonderful companion while travelling.