Presentation of the ToCHI paper at the 33rd Annual ACM Conference on Human Factors in Computing Systems (CHI 2015) in Seoul. We capture non-uniformity of the movement space of the arm in 11 clusters. The clusters are based on muscle co-activations necessary to produce a movement. However, the clusters turn out to be distinct also in 3D space and orientation. Each cluster has specific performance and physical ergonomics properties. The paper: http://dl.acm.org/citation.cfm?id=2687921 P.S. The slides contain videos and animations which are not displayed by online-viewer, so it is better to watch them offline after downloading.