Aggregation

Your computer is an aggregation of a CPU box, a keyboard, a mouse, a monitor, a CD-ROM driver, one or more hard drives, a modem, a network card, a printer and possibly some speakers.
Your computer is “made up” from a number of different types of components.
If doing away with one of the parts invalidates the whole, you have a composition.

Your computer is an aggregation of a CPU box, a keyboard, a mouse, a monitor, a CD-ROM driver, one or more hard drives, a modem, a network card, a printer and possibly some speakers.