Sony Corporation (commonly known as Sony and stylized as SONY) is a Japanese multinational conglomerate corporation headquartered in Kōnan, Minato, Tokyo.
Its diversified business includes consumer and professional electronics, semiconductors, gaming, entertainment and financial services.
Sony produced the world's first portable music player, the Walkman in 1979. This line fostered a fundamental change in music listening habits by allowing people to carry music with them and listen to music through lightweight headphones. Walkman originally referred to portable audio cassette players and devised by Sony founders Masaru Ibuka and Akio Morita.
The company now uses the Walkman brand to market its portable audio and video players as well as a line of former Sony Ericsson mobile phones.
According to en.wikipedia