This is an easy task!
You can do this!
the first thing you need is a patch / cross ethernet cable.
Plug the cable ports in both computers to test if the cable is okay.
Then the computer will show the connection in
network and sharing center in both computers.
Okay! lets say that you have a desktop computer (D) and a laptop(L). both with windows 7.
And you want to use laptop's internet in desktop.
Go to
Control Panel > Network and Sharing center > and on the left side of your screen you will see
Change Adapter Settings> click on it. And then select your
LAN (the plugged cable network) and
Wireless Network Together.
Then right click and then you will see
Bridge connection option there. Click on it and wait till it connects again to the wireless network.
Then restart your desktop computer.
Enjoy the Internet in the desktop.
If you want to use the same IP address for both computers to connect to the internet to fool the internet as if your computers are connecting to internet like a single machine(Computer) then read my next post.
Stay tuned ^_^..