For my graduate thesis, I developed a notation system for multi-touch interaction. Multi-touch refers to the presence of two or more points of contact with the surface, i.e. multiple fingers on a trackpad. At the inception of my thesis, widespread multi-touch interaction was really in its infancy and I recognized a need to programmatically document all the various gestures. The final notation includes symbology (similar to sheet music) as well as alphanumeric shorthand code.