A presentation program is a computer software package used to display information, normally in the form of a slide show. It typically includes 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.

We use the latest projectors and a very big screen at Clacton & North East Essex Arts & Literary Society

A presentation using PowerPoint.

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. 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. 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.

Presentation programs are used for printing 35 mm slides as well as video projecting.

Many presentation programs come with pre-designed images (clip art) and/or have the ability to import graphic images. Custom graphics can also be created in other programs such as Adobe Photoshop or Adobe Illustrator and then imported. The concept of clip art originated with the image library that came as a complement with VCN ExecuVision, beginning in 1983.

With the growth of digital photography and video, many programs that handle these types of media also include presentation functions for displaying them in a similar "slide show" format. For example, Apple's iPhoto allows groups of digital photos to be displayed in a slide show with options such as selecting transitions, choosing whether or not the show stops at the end or continues to loop, and including music to accompany the photos.

Similar to programming extensions for an operating system or web browser, "add ons" or plugins for presentation programs can be used to enhance their capabilities. For example, it would be useful to export a PowerPoint presentation as a Flash animation or PDF document. This would make delivery through removable media or sharing over the Internet easier. Since PDF files are designed to be shared regardless of platform and most web browsers already have the plugin to view Flash files, these formats would allow presentations to be more widely accessible.

Certain presentation programs also offer an interactive integrated hardware element designed to engage an audience (e.g. audience response systems) or facilitate presentations across different geographical locations (e.g. web conferencing). Other integrated hardware devices ease the job of a live presenter such as laser pointers and interactive whiteboards.