The zoetrope or Wheel of Life is an animation device giving the illusion of motion, it was popular from the 1860s though its principle aspects were described earlier. The device consists of a cylinder that can be rapidly spun, usually by hand. The cylinder has a number of vertical viewing slots, on the inside of the cylinder there is a strip of images showing phases of movement. When the cylinder is spun the strip is in continuous motion, the slits provide a scanning effect thus the eye sees a series of images in rapid succession giving the illusion of motion. The effect was often, wrongly, described as persistence of vision, and is now described by the Phi phenomenon.

The cylinder normally has 13 viewing slots and the paper strips have the same number of images, with this arrangement the figures or images are seen to be in a fixed position. If the number of images is less than the number of slots the images show a slow motion effect, they move in the reverse direction to the spin of the cylinder, if the number of images is greater than the number of slots the slow motion is in the opposite direction. Some strips utilise this effect by having two sets of related images, (e.g. a monkey jumping on a ball), one set might have 12 images the other 14.

Each image is distorted due to the motion, to correct for this the images were drawn with an exaggerated width.