Since the introduction of photography in the mid-nineteenth century, the subject of play is one of the most photographed. Parents take pictures of their children at play with toys, at public playgrounds, with their animals, or dressed in costume. Adults also photograph each other while vacationing, celebrating a holiday, and during impromptu family gatherings. These photographs record some of the happiest moments of childhood and adulthood; they demonstrate the history and commonality of play in our culture.
Stereoscopic photography appeared around 1865, as photographers strove for more realistic, three-dimensional imagery. These double pictures were viewed with a stereoscope, and the pictures themselves are called "stereographs." They remained popular, as a form of entertainment, through 1920. Often mass-produced, stereograph subjects included national landmarks, travel, and humor.