IS Recommended Modems. Internal A modem can be either an external device or a card installed inside the machine. An external modem is a stand-alone unit connected to your computer with a serial cable. Another cable connects the modem to a telephone jack. You must also plug the modem into an electrical outlet.
Internal modems are more likely to be found in portable computers.
A cable from the back of the computer plugs directly into a telephone jack. Internal modems do have disadvantages. Moving the modem to a different machine is tedious. Resetting an internal modem usually requires rebooting the machine. Troubleshooting is more difficult and requires that you take the entire computer to the shop.