First Recording ever made!
The first recording was made by Thomas Edison in 1877. His first machine had a cylinder turned by a hand crank. There was also a horn and a blunted needle. At the small end of the horn, there was a flexible cover.
Sound waves that entered the large end of the horn moved this cover one way or another. To this, the stylus was attached. It moved up and down with the sound waves too.
The cylinder was covered by a layer of tin foil. The stylus pressed against this foil and gears moved the horn with its attached stylus slowly along the cylinder many times, it made a crease in the tin foil.
When someone sang or spoke into the horn, it made the stylus move up and down. The stylus made a deeper groove in the tin foil when it was down, a lighter crease when it was in an upward position. The changing depth of the groove was the pattern of the sound waves made by a person singing or talking. It was the record of the sound.
To play the record, the stylus and horn were moved back to the beginning of the groove. As the stylus followed the groove, it caused the flexible cover in the horn to vibrate in the same pattern. This made the air in the horn move to-and-fro, and this made a sound like the original sound recorded.