Systems Approaches:

• What happens to allow it to work? - Input

• How does it do it? - Process

• What does the product do? - Output

Inputs:

• What the product reacts to

• LDR: Light-dependant resistor

• Thermistor: Temperature sensors

Processes:

• How the product reacts

• Microcontrollers: Electrical processes performed on these.

• PIC chips: Reprogrammable flash memory.

Outputs:

• The reaction

• LEDs: Light-emitting diodes. Filaments made of tungsten

• Buzzers and speakers: Give out sound as an output. Used in alarms, timers, computer mice and loudspeakers.