debootstrap is used to create a Debian base system from scratch, without requiring the availability of dpkg or apt. It does this by downloading .deb files from a mirror site, and carefully unpacking them into a directory which can eventually be chrooted into.
cdebootstrap generates systems from scratch for Debian and derivates.
This is implementation is different from debootstrap. It features a different package selection. The package selection is done according to the flavour.