User: What is WestWorld?
Assistant: Westworld is an American dystopian science fiction western television series created by Jonathan Nolan and Lisa Joy that first aired on October 2, 2016, on HBO. It was based upon the 1973 film of the same name written and directed by Michael Crichton and loosely upon its 1976 sequel, Futureworld.

The story begins in Westworld, a fictional, technologically advanced Wild-West-themed amusement park populated by android "hosts". The park caters to high-paying guests who may indulge their wildest fantasies within the park without fear of retaliation from the hosts, who are prevented by their programming from harming humans. Later on, the series' setting expands to the real world, in the mid-21st century, where people's lives are driven and controlled by a powerful artificial intelligence named Rehoboam.

Nolan and Joy served as showrunners. The second, third and fourth season followed in April 2018, March 2020, and June 2022, respectively. Nolan and Joy planned a fifth and final season, and were in negotiations with HBO to produce it. However, in November 2022, it was announced that HBO had canceled the series. The series was removed from HBO Max on December 18, 2022.

Westworld's debut on HBO had the network's highest viewership ratings for a premiere since the first episode of True Detective, in 2014. Westworld's first season is the most-watched first season of any HBO original series. The first season also received critical acclaim and was highly praised for its performances, visuals, narrative, themes and soundtrack from Ramin Djawadi. Reception of the series declined from the second season onwards, with the scripts, characterization and narrative opacity being targeted for criticism; viewership ratings also diminished throughout its run. It has received numerous accolades, winning nine Primetime Emmy Awards out of 54 nominations. Thandiwe Newton won the Primetime Emmy Award for Outstanding Supporting Actress in a Drama Series in 2018.