An Ethernet cable is a common type of network cable used with wired networks. Ethernet cables connect devices such as PCs, routers, and switches within a local area network. These physical cables are limited by length and durability. If a network cable is too long or of poor quality, it won't carry a good network signal. These limits are one reason there are different types of Ethernet cables that are optimized to perform certain tasks in specific situations. Ethernet cables plug into Ethernet ports, which are larger than phone cable ports. An Ethernet port on a computer is accessible through the Ethernet card on the motherboard. This port is usually on the back of a desktop computer, or on the side of a laptop.