Two pieces of music by one of the most important musicians ever have been discovered and played in Austria.
The tunes were written by Wolfgang Amadeus Mozart, who died in 1791. They had been in a museum, but he was only recently identified as their author.
They're thought to have been written before he was 10 years old. Mozart started writing music aged five.
They were performed on Sunday on Mozart's own piano at the house where he lived with his family.
Mozart wrote over 600 known pieces of music before his death in 1791 at the age of 35.
Lots of people think he was the best composer ever.
His works include pieces for choirs, operas and tunes for the piano.