Jim Smiley is a fictional character created by author Mark Twain in his short story "The Celebrated Jumping Frog of Calaveras County." Smiley is known for his penchant for betting on anything and everything, showcasing his obsession with gambling. He often engages in various wagers, demonstrating his confidence in the outcomes of his peculiar contests. In the story, Smiley trains a frog named Dan'l Webster to jump higher than any other frog. He uses this frog to win bets against unsuspecting challengers. However, his plans are thwarted when a stranger tricks him, leading to a humorous twist that highlights Smiley's gullibility and the nature of deception in gambling.