There is only one option available under Online, but goodness it is a big one. This is your gateway to the Global Link, and allows you to sync your game up with the Global Link website.

The Game Sync links your copy of Black and White to the Global Link servers, sending your achievements and win records for features such as the Random Matchup.

To use the Online features, you'll need a computer that is connected to the internet and connected to a wireless router.

Game Sync

The first time you use the C-Gear, you'll receive your Game Sync ID. Once you have been issued one, you'll need to register it on the Pokemon Global Link. Once you've done that, you can access all the features the Global Link has to offer, including the Dream World and Global Battle Union. To visit the Dream World, all you need to do is click on Game Sync and tuck a Pokemon into bed from one of your boxes (party Pokemon cannot be tucked in). Then, you can explore the Dream World. Only one Pokemon may be tucked in a time, and it takes a day for the Game Sync to recharge.