How many Jeopardy categories are there?

13

Everyone knows that Jeopardy! is an American television game show.  The main idea is that the contestants compete in a quiz game comprising three rounds: the Jeopardy! round, the Double Jeopardy! round, and the Final Jeopardy! round.  There are 13 Jeopardy categories: 6 in Jeopardy round, six in the Double Jeopardy and one in the Final Jeopardy.  The questions come from different domains: history and current events, the sciences, the arts, popular culture, literature, and languages.  It is interesting to know that the original daytime version aired in 1964.