20. Sketchpad
Use of light pen
Interactive line drawings
Constraints resolution engine
Object-based computer aided design (CAD)
On a TX-2 computer at MIT Lincoln Lab
69,632 words with 36 bits (~306 KByte)
28. 1 TUI & “NUI”
Tangible and “Natural” User Interfaces
Physical objects combined with digital information
Multi-Touch & Gestures, Lots of sensors, Mobility