Melody is the most critical component in a song. The melody: is the tune, and it comes in various pitches, notes, and organised patterns. Every single note is usually determined by the rhythm of the melody.
Harmony comes into play when pitches are vertically integrated into groups of three notes. Harmony is commonly termed as a chord or triad. Chords harmonise melodies and provide notes which go along with the melody.
With keys, it refers to grouping pitches into families. All notes in a key have something in common. Keys are developed when a first degree (tonic) and fifth-degree (dominant) are combined with meaning and structure to the pitch elements in the song.
This element explains how time works in a song. The metre of the piece develops when recurring pulses of beats are created, and the effects are accented by time. When a song is playing, you can
detect the regularity of the beats in the music, and the metre organises the element of time in the music.
This is the most popular element which everyone is familiar with. Rhythm applies to the way in which time is used in the music. The melody notes have rhythm because of their varying lengths.