Nora Ephron, humorist, film writer/director

Nora Ephron, the humorist, novelist, foodie, and writer/director of films including Sleepless in Seattle, You've Got Mail and Julie & Julia, died Tuesday night in New York. She was 71. The cause was complications from acute myeloid leukemia.

A second-generation filmmaker (her parents were Desk Set scribes Henry and Phoebe Ephron), Ms. Ephron was a throwback to wisecrackers such as Anita Loos and Dorothy Parker, wits who wrapped social observations in humor. Ephron Exhibit A: "When your children are teenagers, it is important to have a dog so someone in the house is happy to see you when you get home." Ephron movies identified trends as they were happening, like the concept of the "chick flick" (see Sleepless in Seattle) and that of "high-maintenance woman" (see her script for When Harry Met Sally . . .). She was a highly sensitive cultural barometer who could, with great accuracy, measure the subtlest changes in the atmosphere.

Born in New York, raised in Beverly Hills, and educated at Wellesley, Ms. Ephron enjoyed one of the most publicly chronicled lives in American arts and letters. Her birth and infancy inspired her parents to write the screenplay Three is a Family, made into a 1944 film. Her letters from college inspired her parents' play Take Her, She's Mine, subsequently made into a 1967 film. She spun her body-image issues into comic gold with her 1972 Esquire essay, "A Few Words About Breasts." And her 1983 novel Heartburn, a thinly disguised version of her marriage and divorce from Washington Post scribe Carl Bernstein, wrung simultaneous laughter and tears. She adapted her novel to the screen for the 1986 film.

After college and an abortive stint as a White House intern during the Kennedy administration, Ephron moved to New York, where she briefly sorted envelopes in the Newsweek mail room. During the 1962-63 newspaper strike, her contributions to a satirical broadside spoofing New York Post columnists caught the eye of Post publisher Dorothy Schiff, who hired Ms. Ephron. There she profiled celebrities such as Doris Day, wrote lifestyle pieces, and broke the news that Bob Dylan had married Sarah Lownds. In 1967, she wed novelist Dan Greenburg. Their marriage ended in divorce in 1976.

When she married Bernstein that same year, she relocated to Washington and almost immediately became pregnant with Jacob, the first of their two sons. While pregnant with their second, Max, she learned that her husband was having an affair. In Heartburn, she would satirize him as a man "capable of having sex with a Venetian blind."

Apart from her sons, the most important thing she got out of the marriage was learning how to write a screenplay. She and Bernstein tried their hand at rewriting William Goldman's screenplay of All the President's Men, the book written by Bernstein and Bob Woodward. She later said that "retyping Goldman" was the best education in story and dialogue structure a screenwriter could ever have. She and Alice Arlen collaborated on the screenplay for Silkwood (1983), which won her the first of three Oscar nominations. The others were for Sleepless and When Harry Met Sally . . . . She and Bernstein divorced in 1980.

She moved back to New York, continued writing essays (collected in such books as Crazy Salad, I Feel Bad About My Neck, and I Remember Nothing). In 1987, she wed crime writer Nicholas Pileggi (WiseGuys) and commenced an original screenplay called When Harry Met Sally. . . (1989), a romantic comedy that asked the question, "Can friends be lovers?" and answered in the affirmative.

Ms. Ephron made her directorial debut in 1992 with This is My Life, her adaptation of Meg Wolitzer's novel . Wolitzer eulogized her Tuesday: "She was the best, an inspiration to so many people and a great, great friend."

Ms. Ephron took to directing like Julia Child to butter, scoring huge hits with Sleepless in Seattle (1993) and You've Got Mail (1998). The latter was the first movie about e-mail. Julie & Julia (2009), her last movie hit, parallel stories of how cookbook author Julia Child inspired blogger Julie Powell, was the first about blogging.

Many of Ms. Ephron's friends noted at the time of Julie & Julia that the loving and supportive relationship between Julia and Paul Child (Meryl Streep and Stanley Tucci) strongly resembled that between Ms. Ephron and Pileggi. At the time of Ms. Ephron's death, they had been married 25 years. In that movie, Paul Child toasts his wife, "You are the butter to my bread; you are the breath to my life."

Ms. Ephron liked to joke that though she was raised Jewish, her religion was butter.

She is survived by her husband, her sons, and her sisters and frequent collaborators, Delia, Amy, and Hallie Ephron.