Little in science has created as much interest, excitement, and controversy in the past decade as holography. Holography, or wavefront reconstruction as it was first called, was invented by Dennis Gabor in 1948 in an attempt to improve the resolution of images obtained with an electron microscope. Although Gabor was unable to demonstrate his technique with electron waves, he was able to do so with visible light. The most serious problems Gabor and other early holography experimenters encountered was the pre-sence of a twin image and the absence of a light source suitable for making holograms. Within a decade after its invention, holography appeared destined for obscurity. However, in the early 1960's Leith and Upatnieks at the University of Michigan demonstrated a new approach to holography based on communications theory techniques that made it possible to eliminate the twin image and hence gave higher resolution images than previously available. At about the same time lasers were being developed that provided the coherent light required for making holograms. By 1964 or 1965 holography was causing much interest in the scientific community, and investigators at numerous universities and industries began studying and inventing new holographic techniques. Between 1964 and 1968 more than 500 papers and articles were written on holography. Unfortunately, many of the early predictions on the use of holography failed to materialize, and by 1968 much of the glamor earlier associated with holography began to disappear, contracts were no longer awarded simply because the title contained the word "hologram," and many of the investi-gators began to study other fields.