It's finally here: Nintendo's Wii U is coming to the world on Sunday. It's been a long time coming, but the wait isn't really for the games: Ever since we saw that gamepad—that weird, freakish, beautiful, intimidating, what-the-hell-do-I-do-with-it-who-cares-I-want-it controller—we've been obsessed with the Wii U.

How'd they come up with it? What, exactly, is it capable of? And how the hell did we—gamers, developers, designers, Nintendo, the world—get here to begin with?

Well, that's the thing: The more we stared at it, the more we realized that this thing's been in the making for a very long time. Just like every Nintendo controller has. While—unlike other systems—their controllers vary in design wildly from console to console, they all share a very, very distinct DNA. 

As such, this is The Evolution of the Nintendo Controller: 15 Gamepads That Changed Nintendo Forever.

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