How do I route internet from one computer to another via ethernet cable?

I plan on working on computers at home,but our router is in a different room.

I have a desktop with built in wireless, and want to route the internet it recieves to the computer I would be working on VIA ethernet cable. I read somewhere that I need a crossover cable? How would I set up this system with the cable, and what hardware do I needin the computer that has the wifi connection?