What is primarily used to connect peripheral devices like keyboards and mice to computers?

The primary technology used to connect peripheral devices such as keyboards and mice to computers is USB (Universal Serial Bus). USB was designed specifically to facilitate communication between devices and a host, such as a computer. It provides a standardized connector and cable system that simplifies the process of linking various peripherals to the computer.

USB supports a wide range of devices beyond simple input devices, such as printers, external drives, and even some audio and video devices, ensuring compatibility across numerous types of hardware. The versatility, ease of use, and broad adoption of USB technology have made it the standard for peripheral connections.

Other options, while useful in their respective functions, are not primarily intended for connecting standard peripherals. HDMI (High-Definition Multimedia Interface) is primarily used for transmitting high-definition audio and video signals, Ethernet is used for network connectivity, and Thunderbolt can connect various high-speed devices but is often more associated with high-performance storage and displays rather than basic input devices. Thus, USB is the definitive answer for connecting keyboards and mice.