RJ-45 and RJ-11 Connectors.
RJ-11 connectors are found on your telephone. This connector is used for dial up modems. it is smaller than the RJ-45 connectors which is used for network cabling. Ethernet cables have the RJ-45 connectors. These are larger then the RJ-11.
Keep an eye out soon I will have a post on how to create your own Ethernet cable.