In The Big Lebowski (1998), The Dude’s first name is Jeffrey.
The character is introduced as Jeffrey “The Dude” Lebowski, a laid-back Los Angeles bowler whose quiet routine is disrupted when criminals mistake him for a wealthy man with the same surname. Jeff Bridges played the character, whose relaxed speech, bathrobe, and bowling-centered lifestyle became central parts of the film’s identity.
The Dude is often confused with Jeffrey Lebowski, the wealthy wheelchair-using philanthropist at the center of the kidnapping plot. Both men are called Lebowski, but they are different characters. The nickname belongs to the older film protagonist played by Bridges.
Joel and Ethan Coen wrote and directed the movie. Although its initial theatrical reception was mixed, The Big Lebowski later developed a large cult following, including annual fan festivals and a vocabulary of memorable quotations.