how many levels does it have?
Three
Jeopardy!
The contestants compete in a quiz game comprising three rounds: Jeopardy!, Double Jeopardy!, and Final Jeopardy! 
how much can you wager in final jeopardy 13, 420, and 911 who developed it? Merv Griffin
wiki:826413
Jeopardy! [SEP] Gameplay
Three contestants each take their place behind a lectern, with the returning champion occupying the leftmost lectern (from the viewer's perspective). The contestants compete in a quiz game comprising three rounds: Jeopardy!, Double Jeopardy!, and Final Jeopardy! The material for the clues covers a wide variety of topics, including history and current events, the sciences, the arts, popular culture, literature, and languages. Category titles often feature puns, wordplay, or shared themes, and the host will regularly remind contestants of topics or place emphasis on category themes before the start of the round. All clues in the show are presented as "answers", and responses must be phrased in the form of a question.