David Lightman is a fictional character from the 1983 film WarGames. He is portrayed as a high school student and computer whiz who accidentally hacks into a military supercomputer while searching for new video games. His actions inadvertently lead to a potential nuclear crisis, showcasing the dangers of technology and the importance of responsible computer use. In the film, David is played by actor Matthew Broderick. The story highlights themes of youth, technology, and the consequences of unintended actions. David's character ultimately learns valuable lessons about the power of technology and the need for caution in its use.