A patch cable or patch cor (sometimes patchcable or patchcord) is an electrical or optical cable, used to connect ("patch-in") one electronic or optical device to another for signal routing. Devices of different types (ie: a switch connected to a computer, or switch to router) are connected with patch cords. Patch cords are usually produced in many different colours so as to be easily distinguishable, and are relatively short, perhaps no longer than two metres. Types of patch cords include microphone cables, headphone extension cables, XLR connector, RCA connector and ¼" TRS connector cables (as well as modular ethernet cables), and thicker, hose-like cords (snake cable) used to carry video or amplified signals. However, patch cords typically only refer to those short ones used with patch panels.