USB’s trident symbol indicates a USB connection, but on its own it usually refers to older USB 2.0 technology rather than revealing every capability of a port or cable. Understanding labels, symbols and colours matters because USB connections can vary widely in data-transfer speed, charging ability and display support, affecting which accessories work best with a computer.

USB 2.0 offers up to 480Mbps and is suitable for low-speed devices such as keyboards and mice. Later versions originally called USB 3.0, 3.1 and 3.2 provide 5Gbps, 10Gbps and 20Gbps respectively, now marketed by speed; their symbols may include ‘SS’ and a number. Black or white commonly denotes USB 2.0, blue usually indicates 5Gbps, while red or yellow ports may supply power when a computer is off, though colour conventions are not fully standardised.