Sega v Nintendo: the console war that changed the video game industry
The battle between video game giant Nintendo and upstart Sega arguably laid the foundation for the future of the video game industry.
In the late 1980s, Nintendo, a Japanese company, revived the video game industry in the United States after a crash wrecked Atari's prospects and other companies were turning away from console games.
By 1990, Nintendo had a virtual monopoly on the industry with popular games like Donkey Kong and Super Mario.
Sega, another Japanese company that had tried - and failed - to compete effectively with Nintendo in the past, was determined to overtake the video game giant.
It hoped its new mascot, Sonic the Hedgehog, with his speed and attitude, was the Mario killer it was looking for, says Blake J Harris, author of the new book Console Wars.
He told the BBC that Sega's philosophy and marketing changed the industry and proved that video games were not just for kids.
Produced by Ashley Semler and David Botti; filmed by Anna Bressanin
Living Online is a series of video features published every Tuesday on the BBC News website which look at how technology converges with culture and all aspects of our daily lives.