Lecture 3

A computer system contains various elements, each of which affects the user of the system.
Interaction (with or without computer) is a process of information transfer.

Input devices for interactive use, allowing text entry, drawing and selection from the screen:
– text entry: traditional keyboard, phone text entry, speech and handwriting
– pointing: principally the
mouse, but also touchpad,
stylus and others
– 3D interaction devices.

Output display devices for interactive use:
– different types of screen mostly using some form of bitmap display

Output display devices for interactive use
large displays for shared and public use
digital paper may be usable in the near future

Virtual reality systems and 3D visualization which have special interaction and display devices.

Memory
short - term memory : RAM
long - term memory : magnetic and optical disks
capacity limitations related to document and video storage
effect of accessing to memory memory
Processing
the effects when systems run too slow or too fast, the myth of the infinitely fast machine
limitations on processing speed