Elements of music in 20 seconds

1. Harmony: striking a chord of simultaneous notes, here the G Major triad G3, B3, D4.

2. Melody: varying the pitch in a sequence of notes, here the melodic line C4, E4, G4, F4, D4.

3. Rhythm: varying the duration of notes, here for the same melodic line.

4. Timbre: adding texture with harmonic overtones, here enriching the same melody and rhythm.

Ludwig van Beethoven crafted all four elements into a 10-second musical composition. His Bagatelle Number 10, Op. 119 from CE 1822 is played here on an acoustic guitar by Ed Chang:

Timeline of the Human Condition, 42,000 years ago