• Desk-bound displays (CRT, LCD, Plasma, OLED)
• Portable displays (LCD, OLED)
• Displays in helmets , eye glasses , contact lenses
• Projections onto retina
• Wall-mounted displays (rear or front projections, flat panel)

• Speech Audio
• Non-Speech Audio

• Force output

• Special output devices for people with disabilities
  (Braille display, speech, etc.)

• Olfactorial output
  

  Cater to variety of possible output devices