A presentation program is a software package used to display information in the form of a slide show. It has three major functions: an editor that allows text to be inserted and formatted, a method for inserting and manipulating graphic images, and a slide-show system to display the content.
Early presentation graphics software ran on computer workstations, such as those manufactured by Trollman, Genigraphics, Autographix, and Dicomed. It became quite easy to make last-minute changes compared to traditional typesetting and pasteup. It was also a lot easier to produce a large number of slides in a small amount of time. However, these workstations also required skilled operators, and a single workstation represented an investment of $50,000 to $200,000 (in 1979 dollars).
In the mid-1980s developments in the world of computers changed the way presentations were created. Inexpensive, specialized applications now made it possible for anyone with a PC to create professional-looking presentation graphics.
Originally these programs were used to generate 35 mm slides, to be presented using a slide projector. As these programs became more common in the late 1980s several companies set up services that would accept the shows on diskette and create slides or print transparencies. In the 1990s dedicated LCD-based screens that could be placed on the projectors started to replace the transparencies, and by the late 1990s they had almost all been replaced by video projectors.
The first commercial computer software specifically intended for creating WYSIWYG presentations was developed at Hewlett Packard in 1979 and called BRUNO and later HP-Draw. The first software displaying a presentation on a personal computer screen was VCN ExecuVision, developed in 1982. This program allowed users to choose from a library of images to accompany the text of their presentation.
A presentation program is supposed to help both the speaker with an easier access to his ideas and the participants with visual information which complements the talk. There are many different types of presentations including professional (work-related), education, entertainment, and for general communication. Presentation programs can either supplement or replace the use of older visual-aid technology, such as pamphlets, handouts, chalkboards, flip charts, posters, slides and overhead transparencies. Text, graphics, movies, and other objects are positioned on individual pages or "slides" or "foils". The "slide" analogy is a reference to the slide projector, a device that has become somewhat obsolete due to the use of presentation software. Slides can be printed, or (more usually) displayed on-screen and navigated through at the command of the presenter. The slides can also be saved as images of any image file formats for any future reference. Transitions between slides can be animated in a variety of ways, as can the emergence of elements on a slide itself. Typically a presentation has many constraints and the most important being the limited time to present consistent information.