The Matrix is an illusion.
It is maintained by some old dude who lives in a room full of TV screens. He is the perfect offspring of the three smartest mathematical geniuses combined into a single organism. Sperm, egg, and who the hell knows what the third being is.
The Matrix is an illusion that is balanced by the old dude. On one side of the scale are the humans. On the other side of the scale are the machines. If the scale is tipping in favor of either side, then the old dude uses some crazy voodoo math shit to make sure the scale doesn’t tip too far.
While the Matrix is an illusion, it was designed to keep the minds of humans preoccupied while the evil machines of the future obtained energy from the bodies of man.
So I guess the purpose of the Matrix is to keep the minds of humans fresh, otherwise they spoil. I also guess that a spoiled brain yields no evil robot energy. Looks like Zombies are on to something… o_O