Short for Registered Jack-45, an RJ-45 is an 8-pin connection used for Ethernet network adapters. This connector resembles the RJ-11 or 6-pin connector used with telephones in the United States, but they’re completely different. The picture is of an RJ-45 connector separated from the cable.

This connector most commonly connects to the end of Cat 5 cable, which connects between a computer network card and a network device, such as a network router.

Computer acronyms, Connection, Network terms

  • How to make a network cable.
  • Network and network card help and support.