Apple iMac (Early 2009) - Manual (Page 11)

Chapter 1 Ready, Set Up, Go 11
Step 2: To access the Internet or a network, connect one end of an Ethernet cable
to the Ethernet port on your iMac. Connect the other end to a cable modem, a DSL
modem, or a network.
Your iMac comes with AirPort Extreme technology for wireless networking.
For information about setting up a wireless connection, choose Help > Mac Help,
and search for “AirPort.”
To use a dial-up connection, you need the external Apple USB Modem, available from
the online Apple Store at www.apple.com/store or from an Apple Authorized Reseller.
Plug the Apple USB Modem into a USB port on your iMac, and then use a phone cord
(not included) to connect the modem to a phone jack.
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