<P> A slide show may be a presentation of images purely for their own visual interest or artistic value, sometimes unaccompanied by description or text, or it may be used to clarify or reinforce information, ideas, comments, solutions or suggestions which are presented verbally . Slide shows are sometimes still conducted by a presenter using an apparatus such as a carousel slide projector or an overhead projector, but now the use of an electronic video display device and a computer running presentation software is typical . </P> <P> Slide shows had their beginnings in the 1600s, when hand - painted images on glass were first projected onto a wall with a "magic lantern". By the late 1700s, showmen were using magic lanterns to thrill audiences with seemingly supernatural apparitions in a popular form of entertainment called a phantasmagoria . Sunlight, candles and oil lamps were the only available light sources . The development of new, much brighter artificial light sources opened up a world of practical applications for image projection . In the 1800s, a series of hand - painted glass "lantern slides" was sometimes projected to illustrate story - telling or a lecture . Widespread and varied uses for amusement and education evolved throughout the century . By 1900, photographic images on glass had replaced hand - painted images, but the black - and - white photographs were sometimes hand - colored with transparent dyes . The production of lantern slides had become a considerable industry, with dimensions standardized at 3.25 inches high by 4 inches wide in the US and 3.25 inches square in the UK and much of Europe . </P> <P> "Magic lantern shows" also served as a form of home entertainment and were especially popular with children . They continued to have a place among commercial public amusements even after the coming of projected "moving pictures". Between films, early movie theaters often featured "illustrated songs", which were community sing - alongs with the lyrics and illustrations provided by a series of projected lantern slides . Theaters also used their lanterns to project advertising slides and messages such as "Ladies, kindly remove your hats". </P> <P> After 35 mm Kodachrome color film was introduced in 1936, a new standard 2 × 2 inch (5 × 5 cm) miniature lantern slide format was created to better suit the very small transparencies the film produced . In advertising, the antique "magic lantern" terminology was streamlined, so that the framed pieces of film were simply "slides" and the lantern used to project them was a "slide projector". The old - fashioned magic lantern show became an up - to - date "slide show". </P>

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