Public sex is sexual activity that takes place in a public context. It refers to one or more persons performing a sex act in a public place, or in a private place which can be viewed from a public place.
Such a private place may be a back yard or a bedroom with the curtains open. Public sex also includes sexual acts in semi-public places where the general public is free to enter, such as shopping malls. Public sex acts can be performed in cars (colloquially called "parking"), on beaches, in forests, theatres, buses, streets, toilet cubicles, or cemeteries.