Melody

 Melody is a sequence of musical notes that are played or sung in a particular order to create a distinct and recognizable tune. It is often considered the most memorable and expressive part of a piece of music. Melodies are usually characterized by their rhythm, pitch, and movement from one note to another, forming a cohesive and pleasing sound.

In simpler terms, when you hum or sing a song, the part you are most likely remembering and singing is the melody. It is often supported by harmonies and rhythms, but it remains the leading, standout feature of most musical compositions.