Rhythm is the regular, repeating pattern of sounds in music. It is created by the alternation of stressed and unstressed beats, and can be expressed in a variety of ways, including through tempo, meter, and syncopation.
Melody is a succession of musical notes that form a recognizable pattern. It is what we typically think of as the “tune” of a song, and can be created by a single instrument or voice, or by multiple instruments playing together.
Rhythm is more fundamental than melody because it is the basic structure that underlies all music. It is what gives music its sense of movement and pulse. Without rhythm, music would simply be a series of random sounds.
Melody, on the other hand, is a more complex element of music that is built upon rhythm. It adds a layer of interest and expressiveness to music, but it is not essential for music to exist. There are many examples of music that feature rhythm without melody, such as drum solos, electronic music, and some forms of avant-garde music.