Pinan Yondan
The second word in each kata name denotes which Pinan it is. They were developed by the great Shuri Te master Yasutsune “Anko” Itosu. Itosu developed these forms as part of the physical education program in Okinawan schools. He found that kids could benefit greatly from karate but had to break it down into a simpler form.
There is some debate over which kata influenced the Pinans the most. It is widely accepted that the forms Kusanku (Kanku Dai) and Channan were the true source. Kusanku is still widely practiced but Channan has been lost to history.