- analogue Continuous data, eg the second hand on an analogue watch displays each second and the space in between.
- data Values, typically letters or numbers.
- digital Information stored as discrete values usually represented as numbers. This contrasts with analogue data which is represented by continuous data, usually in waves.
- infrared Radiation which transfers heat energy. Part of the electromagnetic spectrum with a longer wavelength than light waves but a shorter wavelength than radio waves.
- output Either an exit or changes which exit a system and which activate or modify a process.
- processor Shorthand for central processing unit (CPU).
- program Sequences of instructions for a computer.
- sensor A device that measures a physical quantity and converts it into a signal to be read and interpreted.