1st July 1979: Sony Corporation releases the Walkman portable cassette player in Japan

While retailers were unsure about the demand for a playback-only cassette device, Sony conducted street demonstrations and distributed units to celebrities and influencers that led to the Walkman selling over 30,000 units in Japan within its first two months.

9th April 1860: First known audio recording made by French inventor Édouard-Léon Scott de Martinville on his phonautograph

Scott developed the phonautograph, which used a horn to collect sound waves and direct them onto a membrane, and made a recording of a fragment of the song “Au Clair de la Lune” on 9 April 1860.