He is one of the world's most celebrated game designers, and is often called the father of modern video gaming. His titles are characterized by refined control-mechanics and imaginative worlds in which the players are encouraged to discover things for themselves, as well as basic storylines, which had been almost unheard of before he introduced one of the first, featuring Mario.
In 1980, the fairly new Nintendo of America was looking for a hit to establish itself as a player in the growing arcade market. After successful location tests using prototypes, NoA CEO Minoru Arakawa ordered a very large number of units of Radar Scope, an arcade game. However, by the time the arcade machines could be produced and shipped to the U.S., interest had vaporized, causing Radar Scope to be a huge flop. To stay afloat and clear the costly inventory of Radar Scope, Nintendo of America desperately needed a smash-hit game that the unsold machines could be converted to play. Yamauchi assigned Miyamoto, the only person available, the task of creating the game that would make or break the company.
After Miyamoto had consulted with some of the company's engineers although he had no prior programming experience, and composed the music himself on a small electronic keyboard, Donkey Kong was fully conceptualized. When the game was complete, the chips containing the new program were rushed to the U.S. and Nintendo employees worked around the clock to convert the "Radar Scope" machines. It was fortuitous that Nintendo had so many units on hand, because Donkey Kong was an overnight success, and not only saved the company, but introduced the character who more than any other would be identified with Nintendo.
The three most famous characters Miyamoto created for the game were Donkey Kong, Jump Man, and Pauline . It was Mario, a character who descends from Jump Man, that has found the most success, and since his debut in Donkey Kong he has appeared in more than 100 games spanning over a dozen gaming platforms.
-Wikipedia.org