Trebek presided over the beloved quiz show for more than 30 years.
He was a master of the format, engaging in friendly banter with contestants and appearing genuinely pleased when they answered correctly.
He was also able to move the game along in a brisk no-nonsense fashion whenever people struggled for answers.
In July, Trebek celebrated his 80th birthday not long after marking 36 years with "Jeopardy!" in September and one year since his cancer diagnosis.
In November 2019, Trebek became emotional over a contestant's answer.
The touching moment happened in a "Tournament of Champions" episode when contestant Dhruv Gaur used his "Final Jeopardy" response to pay tribute to Trebek.
Earlier that year, Trebek and his wife, Jean, sat down with Good Morning America to share their experiences dealing with his pancreatic cancer and a special message to fans.
Many fans were deeply affected by Trebek's diagnosis with stage four pancreatic cancer which he announced in March 2019.
One of them was 32-year-old Michael Kneeter, who has autism.
Trebek called and talked to him for several minutes after Kneeter's mother tracked him down.
Also known for his generosity, in October 2015 Trebek endowed a $1 million scholarship for undergraduates at Fordham University.
Trebek's sense of humor also shined through in the show. In a June 2015 episode, he didn't skip a beat when reading a clue about the classic 90s sitcom "The Fresh Prince of Bel Air."
Alex Trebek was 80 years old.
Information from the Associated Press was used in this report.