Required cabling
You need an Ethernet cable appropriate for your computer. If you do not have one, see technical document 106654: "Ethernet: Cables Used by Macintosh Computers"
Steps to connect
1. Plug one end of an RJ-45 twisted-pair cable into the 10/100Base-T Ethernet port on your computer (Figure 1).
Figure 1 RJ-45 Ethernet Port below Ethernet icon
2. Plug the other end of the twisted-pair cable into an RJ-45 network port on the target device.
The target device may be a router, hub, AirPort Base Station, or another computer. For more information on these options, see technical document 106658: "Creating a Small Ethernet Network"
After connecting
After connecting, you may wish to perform File Sharing. For more information, see technical documents:
106461: "Mac OS X: File Sharing"
106657: "Mac OS 8, Mac OS 9: File Sharing"