Pac-Man was designed to have no ending – as long as the player keeps at least one life, he or she should be able to play the game indefinitely. However, a bug keeps this from happening: Normally, no more than seven fruit are displayed at the bottom of the screen at any one time. But when the internal level counter, which is stored in a single byte, reaches 255, the subroutine that draws the fruit erroneously "rolls over" this number to zero, causing it to try to draw 256 fruit instead of the usual seven. This corrupts the bottom of the screen and the entire right half of the maze with seemingly random symbols, making it impossible to eat enough dots to beat the level. Because this effectively ends the game, this "split-screen" level is often referred to as the "kill screen". Emulators and code analysis have revealed what would happen should this 255th level be cleared: The fruit and intermissions would restart at level 1 conditions, but the enemies would retain their higher speed and invulnerability to power pellets from the higher stages.
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Uncovering the Dirtiest Lie in Video Game History
In December 1982, an 8-year-old boy, Jeffrey R. Yee, supposedly received a letter from U.S. President Ronald Reagan congratulating him on a worldwide record of 6,131,940 points on Pac-Man
FALSE impossible The highest score achievable in Pac Man is only 3,333,360 points, due to a game-ending byte-overflow bug in the screen rendering code when level 256 is reached. This causes a "split-screen" effect, rendering the game unwinnable. Even President Ronald Reagan was fooled by this lie; he sent Jeffrey a letter of congratulations.
Note:if you don't believe the story,Google Jeffrey R. Yee, it is a pretty unknown video game fact.And i been knowing and it came to a shock to me.