Peripherals are external devices that connect to a computer to enhance its functionality. Common examples include keyboards, mice, and printers. These devices allow users to interact with the computer and receive output in various forms, making them essential for everyday computing tasks. In addition to input and output devices, peripherals can also include storage devices like external hard drives and USB flash drives. They play a crucial role in expanding a computer's capabilities, enabling users to perform a wide range of tasks, from gaming to professional work.