What defines a peripheral device?

A peripheral device is defined as a component that connects to a computer system to add functionality. The correct answer highlights that peripheral devices communicate with the computer through various interfaces, such as USB or HDMI ports, enabling interactions that extend the system's capabilities.

Peripheral devices can be classified into input devices, output devices, or storage devices, but the defining characteristic is their connection via a data port. This connection allows the peripheral to work in conjunction with the computer, enhancing its versatility and performance.

While independent operating devices or built-in components are critical for a computer's function, they are not classified as peripherals. Similarly, the input-only classification does not encompass the full scope of peripheral devices, as many peripherals serve different purposes, including both input and output functionalities.