The Evolution of the User Interface

Goals
Definition of a User Interface
- visible piece of software which makes the services of the underlying system easier to utilize efficiently (and effectively)
People and Machines: Evolution
1. programmer == designer == engineer == user
2. batch mode to increase utilization
3. time-sharing: an illusion of many computers
4. line-oriented interface
  1. enter system commend and arguments
  2. must know all the commands
  3. man pages in unix
  4. the human factor and errors (data entry)
5. GUI: graphical user interface (WYSIWYG)
  1. pictures convey more information
  2. menus and icons: multiple choice
  3. need pointing device (e.g., mouse)
6. Future???
  1. voice commands
  2. speech recognition
  3. direct thought
  4. further evolution to anticipate commands/automate
Guidelines for System Design
1. transparency: not get in the way
2. forgiving: avoid, or at least minimize severe user mistakes
3. visually-oriented: higher bandwidth
Data and Programs
1. traditional:
  - data: static, inert, passive
  - program: dynamic, active
  - example: paint and a "power painter"
2. modern (1999)
  - object-oriented: program embedded in the data
  - Example: spreadsheet is user-configurable
  - HTML : Hypertext Markup Language for interface into the World Wide Web