A tangible user interface (TUI) is a user interface in which a person interacts with digital information through the physical built environment|environment. The initial name was Graspable User Interface, which no longer is used.
One of the pioneers in tangible user interfaces is Hiroshi Ishii (computer scientist)|Hiroshi Ishii, a professor in the Massachusetts Institute of Technology|MIT Media Laboratory who heads the Tangible Media Group. His particular vision for tangible UIs, called Tangible Bits, is to give physical form to digital information, making bits directly manipulable and perceptible. Tangible bits pursues seamless coupling between these two very different worlds of bits and atoms.