The best game ever? Maybe. The most influential 3D game ever? Definitely.

Originally designed for the Super NES's FX Chip (the same one responsible for Star Fox and those cool effects in Yoshi's Island), it was instead put onto the 'Ultra 64' (as the 64-bit console was called at the time), due to hardware limitations. The game featured an emphasis on exploration and in order to do so, a revolutionary manual camera system was added, which has since become an important part of any 3D game.
The game also featured the official debut of Charles Martinet as the heroic plumber. He was previously the voice of Mario in 'Mario Teaches Typing 2' for PC, and before that, at various trade shows, with a 3D Mario head talking to visitors via motion capture and hidden camera. (This was done more recently at E3 in 2006, as can be watched at [link])

There is nothing like Super Mario 64. Full freedom to explore any of the courses, combined with challenging objectives, an amazing arsenal of athletic moves and attacks. Let's face it: the game is just plain fun. Even after you defeat the final Bowser battle, there's still 50 more stars to collect! Excellent replay value. A true classic.
Sadly, this would be Mario's last platformer until 'Super Mario Sunshine', six years later.

And, for the record, Luigi is NOT in this game. He didn't make his 64-bit appearance until 'Mario Kart 64' a year later. He is in the DS remake, however.

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