USB switches facilitate the use of a terminal with multiple desktop computers or laptops. You can access an external hard drive from two computers, store and retrieve data from it. USB hubs expand devices by giving them more USB ports. Various models can be mounted on the wall, desk or directly on the PC. This facilitates the operation of ports that are otherwise difficult to access. For additional convenience and enhanced functions a changeover switch is provided. This allows the operation of multiple computers with a single keyboard, mouse and monitor. This, inter alia, bears the advantage that a computer can be outsourced from offices to reduce emissions and to avoid noise in these spaces.