K. 265/300e, is a piano composition by Wolfgang Amadeus Mozart, composed when he was around 25 years old (1781 or 1782). This piece consists of twelve variations on the French
folk song "Ah! vous dirai-je, Maman". The French melody first appeared in 1761, and has been used for many children's songs, such as "Twinkle Twinkle Little Star", "Baa, Baa, Black Sheep"
and the "Alphabet Song".

Quotes from Wikipedia