"Microform or microformat" is a general term used to describe the microfilm, microfiche, or microprints (micro-opaque) used for the storage of documents that have been photographed and reduced in size in order to conserve space or to preserve materials that deteriorate rapidly.
For information on the history of microfilm: The History of Microfilm: 1839 To The Present [University of California SRLF]
Microfilm: Long strips of transparent plastic, containing photographed pages, rolled onto reels.
Microfiche: Rectangular sheets of transparent plastic, containing rows of images of printed pages. They are stored in envelopes (sleeves) and hold up to 98 page images per fiche).
Super-fiche: Rectangular sheets of transparent plastic, containing rows of images of printed pages. They are stored in envelopes and can hold up to 500 page images per fiche.
Microprint (also known as micro-opaque or micro-card): Rectangular sheets of card stock stored in boxes or in envelopes (sleeves). Though an obsolete microformat, the Libraries retain numerous collections on microprint.