The Microprocessor is built onto a single piece of silicon, known as a wafer or chip, Its size is about 0.5 cm along one side and no more 0.05 cm thick. It can be programmed to perform a great number of information-handling tasks. It can serve as a general-purpose computer for instructional or word-processing use, to control other machines or industrial processes such as making food products, and for hand-held calculators. Its advent was brought about by the progressive miniturisation of integrated circuits and by advances in semiconductor technology.