Q. How can data and instructions are put into the computers?

The data and instructions to a computer are provided by external environment. It determines that input devices are required in computer. The major responsibility of input devices will be to put data in form of signals which can be recognised by system. Correspondingly we require another component that will report results in proper format. This component is known as output device. These components mutually are termed as input/output (I/O) devices.

Additionally to transfer the information, computer system internally requires system interconnections. At present we won't discuss about Input/output devices and system interconnections in details except the information that most general input/output devices are keyboard, printer and monitor and most common interconnection structure is Bus structure.