The use of microscopic images in pathology dates back to the first users of the microscope. As early as the seventeenth century, Antoni van Leeuwenhoek measured the sizes of microscopic objects, including human erythrocytes, using reference objects such as hairs and grains of sand. Drawings from observation and later from the camera lucida were the earliest means of recording microscopic images. With the development of photography in the nineteenth century, photomicrography came into use for the communication and archiving of microscopic images, and it has been the standard for well over a century. The development of electronic imaging in the twentieth century had diverse roots in the fields of astronomy and medical radiology, the television and motion picture industries, the development of electronic copying, publishing, and printing technology, and of course the ascendance of the microcomputer. Only in the last decade has the technology for electronic acquisition, display, and storage of images become generally available, cost-effective and capable of sufficient resolution for effective routine use in pathology.