The good old Sony casette Walkman was quite a revolution. But times change, and with the changing times, the Sony Walkman has lost its place in the sun. Sony has been manufacturing Walkmans since nearly 30 years, the first one came out in 1979. Sony says it has sold over 400million Walkmans worldwide, of these, 200,020,000 were cassette based walkmans. CD and MD based Walkmans will stay in production for the time being.