" A hologram is a flat surface that, under proper illumination,
appears to contain a three-dimensional image. A hologram may
also project a three-dimensional image into the air—a lifelike
image that can be photographed although it cannot be touched.
Because they cannot be copied by ordinary means, holograms are
widely used to prevent counterfeiting of documents such as
credit cards, driver's licenses, and admission tickets. The word
hologram comes from the Greek roots holos meaning whole and
gramma meaning message. The process of making a hologram is
called holography. When a hologram is made, light from a laser
records an image of the desired object on film or a photographic
plate." Each cell of a hologram contains the whole message--the
entire picture. When light is shined on it, it reaches into a
new dimension (e.g. a two dimensional picture becomes three
dimensional). In a normal photograph, each cell contains a
portion of the picture. In a hologram, each cell contains 'the
whole message.' Sheep follow th