One of the big changes for the Wii U is the Nintendo Network. Instead of Friend Codes, the Nintendo Network uses the Nintendo Network ID.
But before you get started, users must create a User Account. For each Wii U console, it's possible to create up to 12 User Accounts. Then, after that, you create your Mii. Next, you create the Nintendo Network ID.
Here's what you'll need to do that: a password, your date of birth, your gender, the area in which you live, and an email address.
This ID is then used with your eShop purchases, Miiverse, and video chat.
There are plans to enable the Nintendo Network ID to be used with other Nintendo hardware. In the future, Nintendo is planning to bring it to PCs and smartphones, giving users the ability to access the eShop and the Miiverse on non-Nintendo hardware.