Apple iMac (Early 2008) - 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, DSL
modem, or Ethernet network.
Note: Your iMac also 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 an external USB Modem, available for purchase
from the online Apple Store at www.apple.com/store or from an Apple Authorized
Reseller.
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