Neil Simon, the playwright whose name was synonymous with Broadway comedy and commercial success in the theater for decades, and who helped redefine popular American humor with an emphasis on the frictions of urban living and the agonizing conflicts of family intimacy, died on Sunday August 26 2018 in Manhattan. He was 91. Mr. Simon wrote for television greats, including Phil Silvers and Sid Caesar. Later he wrote for the movies, too. But it was as a playwright that he earned his lasting fame, with a long series of expertly tooled laugh machines that kept his name on Broadway marquees virtually nonstop throughout the late 1960s and ’70s. Mr. Simon gained a firmer purchase on critical respect in the 1980s with his darker-hued semi-autobiographical trilogy, “Brighton Beach Memoirs” (1983), “Biloxi Blues” (1985) and “Broadway Bound” (1986). In 1991, Mr. Simon won a Tony Award as well as the ultimate American playwriting award, the Pulitzer Prize, for “Lost in Yonkers.” Danny Simon, his brother and older by eight years, was the signal influence on Neil’s career. Together they began writing television and radio scripts, eventually making $1,600 a week providing gags and sketches for Phil Silvers, Jerry Lester, Jackie Gleason and Sid Caesar on “Your Show of Shows” and later “Caesar’s Hour.” The Simon brothers also wrote weekly revues for Camp Tamiment, the summer resort in the Poconos. It was there that Neil Simon fell in love with Joan Baim, a dancer and counselor. By the end of the summer, they were married. Joan, died of cancer in 1973. He met actress Marsha Mason at an audition, and they were married four months later. Mr. Simon, who lived in Manhattan, was married five times. After his divorce from Ms. Mason, he married the actress Diane Lander in 1987. They divorced a year later but remarried in 1990, then divorced again. Mr. Simon married the actress Elaine Joyce in 1999. She survives him, along with his daughters Ellen Simon and Nancy Simon from his first marriage and his daughter Bryn Lander Simon from his marriage to Ms. Lander. He is also survived by three grandchildren and one great-grandson. Danny Simon died in 2005. Mr. Simon graduated from DeWitt Clinton High School in the Bronx and attended New York University as an enlistee in the Army Air Forces Air Reserve training program. He continued his studies at the University of Denver while assigned to a base nearby.