Entitled: "A mon tour" ("My turn"), a woman is peeking through a knothole in a fence watching naked men swimming; a second woman anxiously awaits her turn to look. Color lithograph by Langlum矇. Human sexual activity, or human sexual practice or human sexual behavior, is the manner in which humans experience and express their sexuality. People engage in a variety of sexual acts from time to time, and for a wide variety of reasons. Sexual activity normally results in sexual arousal and physiological changes in the aroused person, some of which are pronounced while others are more subtle.