The Channels by Type ebooks are transcripts of the of The Channels Course taught by Ra Uru Hu in Taos, New Mexico April 15-18, 1999, and is the most extensive work on this topic.
This four book package includes lectures on Creative Channels, Manifesting and Generating Channels, Projected Channels and Understanding the Transits.
Including over 40 hours of lectures on all the channels in a Human Design chart, Ra also gives an in-depth view of how each channel adds to the overall nature of the circuit of which it is part. He discusses at length what quality each channel demonstrates about the entire circuit.