Basic Setup
Wii Friends is designed to enable you to interact with friends through your game console. Through the feature, you can send messages to each other via your consoles, as long as you both have a broadband Internet connection. You can also send photos to each other. The Mii Parade is also designed to enable interaction with friends on the Wii. In particular, it is the place where you can gather all of your Mii characters together with all of your friends' Mii characters.
Gaming
The Wii Friends feature is designed simply as a social function, resembling a social media network that allows you to keep in touch with friends in a way not that different from Facebook or Twitter. It does not have a gaming role. The Mii Parade is part of a gaming function. When you and your friends gather your Mii characters together in the Mii Parade, you can then transport them to the Mii Plaza function. From the Mii Plaza, you can pull Mii characters to the games you are playing to use as your avatars in the games.
Remote
The Wii Friends function allows you to connect remotely with other players so that you can remain connected with friends that you are not with physically. The Mii Parade, meanwhile, serves a function that works with both friends that are remote and friends that are visiting you. If friends are visiting, they simply have to store their Mii characters on their Wii remote and bring it to your console. If the friends are remote, you can gather your characters in Mii Parade using the WiiConnect24 function, which allows you to receive downloads on your consoles.
Making the Connection
You have control over whom you connect with through both Wii Friends and Mii Parade. In both cases, you have to perform certain functions to give your friends access. In the case of Wii Friends, you both have to register each other as friends in your Address Book, using the Wii number on your consoles. Similarly, you can only connect in Mii Parade if either you are sharing a console with your friends or if you have both registered the other in your Address Books.