The film revolves around the question: "Can men and women ever truly be friends?" It popularized the term "high maintenance" as applied to individuals who are difficult to please.
In early 2004, the film was adapted for the stage in a Theatre Royal Haymarket production starring Luke Perry and Alyson Hannigan and also Molly Ringwald and Michael Landes.
Spoiler warning: Plot or ending details follow.
The film is best known for a scene with the two title characters having lunch in a diner. They are arguing about a man's ability to recognize when a woman is faking an orgasm (a largely-improv scene expanded upon at the last moment when originally shooting). Sally claims men can't tell the difference, and to prove her point, she vividly (but fully clothed) demonstrates the skill as other diners watch. The scene ends with Sally casually returning to her meal as a nearby patron, played by Reiner's mother, places her order: "I'll have what she's having."
This scene, filmed at Katz's Deli in New York, was reportedly shot dozens of times, if apparently only for the amusement of the male camera crew, with Meg Ryan's character acting it out each time.