A patch cord (sometimes called a patch cable) is a length of cable with connectors on the ends that is used to connect an end device to something else, such as a power source. One of the most common uses is connecting a laptop, desktop or other end device to a wall outlet. Typically, a patch cord is a copper cable that has an RJ45, TERA or GG45 connector on both ends, although hybrid versions exist that have different types of connectors on the ends. Fiber patch cords are typically called fiber jumpers and are either standard jumpers or mode conditioning jumpers. A patch cord may also be used to connect a switch port or a server to the structured cabling system. Although the new standards do not recommend doing so, sometimes a patch cord is used to connect a server directly to a switch port. When cabling channel is tested, it is a called channel test if patch cords are included, but a permanent link test otherwise. Special connectors are required to test patch cords, which should not be tested using other test methods