A touch user interface (TUI) is a computer-pointing technology based upon the sense of touch (haptics). Whereas a graphical user interface (GUI) relies upon the sense of sight, the TUI enables not only the sense of touch to innervate and activate computer-based functions, it also allows the user, particularly those with visual impairments, an added level of interaction based upon tactile or Braille input.

Ergonomics of human-system interaction -- Part 910: Framework for tactile and haptic interaction

ISO 9241-910:2011 provides a framework for understanding and communicating various aspects of tactile/haptic interaction. It defines terms, describes structures and models, and gives explanations related to the other parts of the ISO 9241 "900" subseries. It also provides guidance on how various forms of interaction can be applied to a variety of user tasks.

Source: ISO