Computer peripherals are external hardware devices that connect to a computer to expand its capabilities. They are controlled by the computer system but are not the core components of the computer. Peripheral devices can be divided into three categories based on their relationship with the computer:

• Input devices: These devices send data or instructions to the computer, such as a mouse, keyboard, graphics tablet, image scanner, barcode reader, game controller, light pen, light gun, microphone, and webcam.

• Output devices: These devices provide output data from the computer, such as a computer monitor, projector, printer, headphones, and computer speakers.

• Input/output devices: These devices perform both input and output functions, such as a computer data storage device (including a disk drive, solid-state drive, USB flash drive, memory card, and tape drive), modem, network adapter, and multi-function printer.

Peripheral devices can be connected to a computer through wired or wireless connections. Wired connections include USB, HDMI, DVI, Ethernet, and serial ports, while wireless connections include Bluetooth, Wi-Fi, and infrared. After a peripheral is connected, drivers may need to be installed to ensure the device functions properly. A peripheral device driver is software that enables a peripheral device to communicate with a computers operating system.

Examples of peripheral devices include printers, speakers, microphones, monitors, mice, keyboards, scanners, external hard drives, flash drives, routers, and modems. Even devices such as smartphones, tablet computers, and wearable devices like fitness trackers and smartwatches can be considered as peripherals, albeit ones that can function independently.