A computer peripheral is any external device that connects to a computer to add functionality or enhance its capabilities. Common examples include input devices like keyboards and mouses, which allow users to interact with the computer, and output devices like printers and monitors, which display or produce results from the computer's processes. Peripherals can be categorized into three main types: input, output, and storage. Input peripherals, such as scanners and microphones, help users provide data to the computer. Output peripherals, like speakers and projectors, convey information from the computer to the user. Storage peripherals, such as external hard drives and USB flash drives, provide additional space for data storage.