"Ave Maria" is a setting of the Latin prayer Ave Maria, originally published in 1853 as "Méditation sur le 1er prélude de piano de S. Bach". The piece consists of a melody by the French Romantic composer Charles Gounod that he superimposed over an only very slightly changed version of Bach's Prelude No. 1 in C major, BWV 846, from Book I of his The Well-Tempered Clavier, 1722. The 1853 publication has French text, but it is the 1859 version with the Latin "Ave Maria" which became popular.
Gounod based the work on Bach's prelude, which is a study in harmony in broken chords. He used the first four measure for a prelude, repeating them for the first entry of the voice. He used Bach's composition, in the version with an inserted measure after the original 22, the so-called Schwencke-measure which was common at the time. To this measure, the voice has a repeated expressive "Maria!". He added a tempo marking, Moderato, pedal markings for the pianist, and dynamic markings.