Transparency (projection)
From Just Solve the File Format Problem
Transparencies are sheets of clear material (often cellulose acetate) on which things can be written, drawn, or printed in order for it to be displayed by projection onto a screen in a manner similar to that used for slide film, only instead of photography, the images are placed on the sheets either by writing by hand with markers, or by printing onto the sheets with computer printers or photocopiers. This method was often used for presenting words and pictures at lectures, meetings, and presentations, but has gone out of style in favor of an all-digital approach of connecting a computer directly to a projector to display what is on its screen, often a presentation created with software such as PowerPoint.
