Mickey Mouse is the face of The Walt Disney Company, originally created as a replacement for Oswald the Lucky Rabbit, who Walt Disney had lost the rights to. With his public debut in Steamboat Willie, one of the first synchronized sound cartoons, on November 18th 1928, Mickey quickly won the hearts of millions of movie-goers and became one of the most beloved and iconic cartoon characters of all time. Mickey Mouse has gone on to star in everything from cartoons and movies to comics and video games.
As far as his personality goes, Mickey is quite an optimist, but he also has quite a mischievous streak that was especially prevalent in his earliest cartoons. Some of his most iconic roles beyond his debut include, among many others, his full color debut in The Band Concert, his stand-out role in Fantasia's The Sorcerer's Apprentice segment, his big TV debut in The Mickey Mouse Club, his guest appearance in Who Framed Roger Rabbit (wherein he finally got to share some screentime with Bugs Bunny of Looney Tunes fame), and his more modern appearances in the Mickey Mouse shorts helmed by Paul Rudish, among a cavalcade of others.