User Interfaces

Human-Computer Interaction

Valle Hansen
valle.hansen@ischool.utexas.edu

University of Texas at Austin

Mick McQuaid
mcq@utexas.edu

University of Texas at Austin

08 Oct 2026

Week SEVEN

Part V of Hornbæk et al. (2025)

Intro

User interfaces are the only part that real people interact with in real settings doing real “tasks”. Therefore, the study of user interfaces has contributions from computer science, electrical engineering, design, and psychology.

Ways of seeing interfaces

  • Englebart: specified augmenting human intellect
  • Shneiderman: identified direct manipulation
  • Weiser: stipulated that the interface should disappear
  • … many others …

Elements

The DIRA model specifies four elements of an interface

  • Devices, such as mice, keyboards, touchscreens, eye trackers
  • Interaction Techniques, mapping input to solutions for interaction problems
  • Representations, how things appear
  • Assemblies, organizations of representations

Interaction Styles

These are combinations of the elements specified in the DIRA model

Command-Line

  • Our textbook is a bit out-of-date on this
  • It says that the command line is entering text and obtaining responses only in text, without interaction capabilities
  • The next frame shows a contemporary command-line interface
  • There are two “window-panes”
  • The left pane shows the user highlighting response text, which is a directory that can be opened by clicking
  • The right pane shows a graphical image, the cover of our textbook

Kitty: a terminal emulator