A flipbook is a small book with a series of printed images which create the illusion of motion when the pages of the book are rapidly flipped. Typically, a flipbook is held in one hand while the thumb of the other flicks the pages, and the user concentrates on the middle of each page. The flipbook relies on a basic optical principle known as persistence of vision to create an animated image. In addition to being amusing, flipbooks also laid the groundwork for motion pictures, and could be considered one of the earliest forms of animation.
Before exploring the flipbook's history, it may help to know how persistence of vision works. The human retina actually retains an image for a brief instant. When a series of images are rapidly presented to the retina, it smooths out the gaps, creating a streamlined animated image. This principle is what allows people to perceive the series of frames in a motion picture as a movie, rather than a set of still photographs. You may have noticed that changes in frame rate and illumination may change the way the animation appears, creating a flicker which can be quite distracting.
The first flipbook was released in 1868 as a kineograph, literally a “moving picture.” The developer of the kineograph realized that images could be presented in a linear sequence, rather than being mounted on a circular drum or disc and rotated. The idea rapidly caught on, and many companies started releasing flipbooks for children and adults alike. Although many modern flipbooks are given away for free, earlier flipbooks were considered miraculous by many people.
Many flipbooks consist of a series of illustrations. Small differences between the illustrations make a brief animated picture when they are rapidly flipped. Others rely on a series of photographs, much like the frames in a movie. The theme of a flipbook may vary, depending on the intended audience; it may illustrate a short story or a brief event, or may even be used in an advertising campaign.
In some parts of the world, a flip book is better known as a flick book, especially in British English. Whatever they call it, many aspiring artists draw their own, and bored school children may ornament their notebooks with flipbooks as well. There are also computer programs which can be used to create a flipbook, stringing together a series of images from a trip, for example.