"When you play the game, it might seem as if the four ghosts are actively chasing you. That's not exactly true. Iwatani intentionally avoided programming them with that purpose, since that would have resulted in Pac-Man zipping around the screen with four ghosts always right behind him.
Instead, it's only Blinky, the red ghost, who doggedly pursues you throughout the game. Pinky, the pink ghost (naturally), simply wants to position itself at a point that's 32 pixels in front of Pac-Man's mouth. The blue ghost, Inky, is seeking to position itself at a similar fixed spot. And Clyde, the orange ghost, moves completely at random."
"What, exactly, does Pac-Man mean?
You may have heard the story about how a pizza with a missing slice inspired Pac-Man's design. But it turns out the game was designed entirely around food.'
"I thought about something that may attract girls," says Iwatani. "Maybe boy stories or something to do with fashion. However, girls love to eat desserts. My wife often does! So the verb ‘eat' gave me a hint to create this game."
That theme continued with the game's name. In Japanese, "puck puck" is akin to the U.S. saying "munch munch". So the original name - Puck-Man - translated as "Munch man". (A savvy Midway Games official changed it to Pac-Man when the game hit the U.S. to discourage vandals from shaving off part of the "P," thereby creating an obscene word.)
http://blog.games.yahoo.com/blog/443-five-things-you-never-knew-about-pac-man