• An Example: If you are implementing a system on a shop floor with inexperienced typists, input devices should be simple, like a mouse, or rugged like a touch screen. If the computer is controlling a large machine, an emergency stop button is required. Disk drives may have problems if there is vibration, or static. ETC.
• An example is software to be written to run on a Nintendo Game System. If this is the case, the software must use the game paddles for input, there is some memory storage (the game programs are stored in ROM chips in the cassettes), Output is visual and audio. Processing could include trajectory calculations, collision detection and scenery drawing.
• Computer software and hardware have both decreased in cost, keep in mind that the cost of software and hardware are often both in the same cost range. (originally hardware was more expensive (1940s-1970s) then software went through an expensive phase (1970s-1990s), but the enlargement of commercial markets has brought economies of scale to both products.