Édith Piaf singing in front of a microphone (1962).

Singing means making music with the voice. Singing is probably the way that music started many thousands of years ago. When people sing they make their voices go high or low. If they do this in a way that uses notes of a scale then they make tunes, called songs. A song, very broadly, is a musical piece, produced by the voice with distinct and fixed pitches and patterns of sound and silence and a variety which often includes repetition.