What is the best way to connect 3 desktop computers to my wireless router?

Question by P C: What is the best way to connect 3 desktop computers to my wireless router?
I have a cable modem and wireless router in my office. There are 3 desktop computers outside that I assume cannot pick up the wireless signal. What is the best way for me to get them online through the wireless? Do I need to buy a device for each computer or is it possible to put another router out there and connect them together?

Best answer:

Answer by Aaron
a wireless adapter that plugs in through the PCI expansion slot or a usb port.

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