On December 6, 1877, Thomas Edison recited "Mary Had a Little Lamb" into his phonograph's tinfoil-wrapped cylinder, producing the world's first playable audio recording of human speech after just a few weeks of invention work.
This breakthrough,
tested in his Menlo Park lab,
amazed witnesses as the machine replayed Edison's voice clearly,
sparking the recording industry's foundation despite the tinfoil's fragility limiting playback to a few repetitions.
The event paved the way for modern audio tech,
evolving from Edison's initial sketches in late 1877 to public demos by early 1878.