"Miserere" is a well-known choral composition by Gregorio Allegri, written in the 17th century. It is a setting of the Psalm 51, which expresses themes of repentance and mercy. The piece is famous for its ethereal beauty and the use of a high soprano voice, often referred to as the "high C," which adds to its emotional impact. The composition was originally performed in the Sistine Chapel during Lent and was kept secret for many years. It gained popularity after Wolfgang Amadeus Mozart transcribed it from memory at the age of 14, helping to spread its fame beyond the chapel.