From the moment our hearts start beating, rhythm is integral to us all. From walking to dancing, from clicking our fingers to tapping our toes, we are all programmed to respond to rhythm. In this film Howard looks at the common rhythmic patterns that have been used by musicians from all cultures, from Brahms to rappers, from the founders of Cuban son to Philip Glass, from Stevie Wonder to Fats Waller.

Why do some rhythms make us want to dance, while others make us feel tranquil? How does rhythm 'work' when there is no obvious pulse, as in much classical music? What links African drumming to J S Bach? Why do virtually all popular singers sing ahead of the beat?

In the late middle ages western harmony started on a journey that would take it in a completely separate direction to that of the music of other parts of the world. It discovered chords, and, over the next seven centuries, began to unlock their harmonic possibilities. In this film Howard looks at how western harmony works, and how, in the present day, it has fused with other forms of music to create new styles.

Chords led to chord progressions, and Howard looks at how familiar patterns of chord progressions give all kinds of music from classical to popular their sense of forward movement. Why do the same chord patterns appear again and again, from Renaissance Italy to the latest chart hit?

Music is usually broken down into melody, rhythm and harmony. But what about the very lowest notes in music, that can have an impact on all three? In this film Howard looks at the abiding fascination musicians and composers have had with the bass.

For half a millennium instrument makers have been trying to construct instruments of all shapes and sizes capable of thudding, sonorous low notes. Only with the arrival of the synthesizer did they succeed in producing a rival to the mighty organ. With disco, dance, and drum 'n' bass, the bass has arrived centre stage.

But bass notes have another, crucial role. Far from just plodding away in the background, bass lines can have a critical effect on the whole structure of a piece of music, helping to drive the chord progressions.