A slide show is a display of a series of chosen information or pictures, done for artistic or instructional purposes. Slide shows are conducted by a presenter using an apparatus, such as a carousel slide projector, an overhead projector or in more recent years, a computer running presentation software. The term "slide" originates from the use of slides which have been around for many years. Slides originally were projected on a screen, for example in a theater by magic lanterns, a practice that later evolved into moving picture shows. Even after the advent of motion pictures, slides continued to be employed for a time between showings of the films, especially to advertise local businesses or maintain theater decorum—for example by requesting that gentlemen remove their hats and refrain from smoking, and urging mothers to remove crying infants from the auditorium.