By transporting data into and out of the computer system, input and output devices allow the computer system to communicate with the outside world. An input device is something you connect to a computer that sends information into the computer and is used to bring data into the system. An output device is something you connect to a computer that receives data and sends it out of the system. I/O devices are commonly used to refer to input/output devices. They are immediately connected to a device controller, which is an electronic module located inside the systems unit. A multimedia computer system's speakers, for example, are directly connected to a device controller known as an audio card, which is then connected to the rest of the system.
