They were not intended for public performance, rather as an aid to his son's compositional development.
The bass material becomes more rudimentary in the second segment, as the treble adopts f of this prelude makes minimal changes to the basic material, mainly brightening it by lifting the slightly altered melody into a higher register.
This prelude is one of the more difficult ones of the set, featuring a constant flurry of notes.
This Prelude has features associated with a trio sonata: it contains two upper lines and a roving bass part underpinning them.
[8] Bach follows a pattern used in many of the pieces in the set, in presenting the main thematic material twice in more or less the same form, then developing it.