Friend Codes are like, phone numbers.. Lol. You have to swap friend codes, to "communicate" with the person. You can send pictures, messages, links, and Mii's. All that junk. You'll enjoy your Wii. It's really fun if you have it online.. I would recommend you to get the Internet Channel. xD But yeah.. for gaming friend codes, you get to swap them, and if they're on their Wii, you can play games with them (if the game is WiFi)!