Hit songs have catchy tunes. It is important to focus on a part of the song that catches the ear of the listener, which is called the ‘hook’. That can be an instrumental riff or a vocal line in the chorus. Melodies should be easy to take in. Staying within the scale, natural majors and minors seem to be quite popular choices. Popular instruments used for the melody include the piano, guitar, brass (such as the trumpet or trombone), organs, synth tones, and more. Believe it or not, whether a song is in a major or minor key can have an impact on its success. Dark and sad songs don’t become hits easily. A lot of the number-one hits of the past year were in a major key. Even though the melody is important, you have to remember that people do get the rhythm mostly out of the drums and bass. The hit songs shouldn’t be too long as people don’t have the attention spans to listen to long tracks.