A general term for any material that contains a small image or micro reproduction of a document.
Shares & Saves. Save. http://www.lib.umn.edu/help/orientation/microforms/mgloss.phtml. Microfilm is a document preservation format that is commonly used in academic-and research-related fields, in order to save pertinent information without taking up a lot of storage space.  To create microform media, a planetary camera is mounted with the vertical axis above a copy that is stationary during exposure. High volume output is possible with a rotary camera which moves the copy smoothly through the camera to expose film which moves with the reduced image. Microform printers can accept positive or negative films and positive or negative images on paper. New machines allow the user to scan a microform image and save it as a digital file-see the section below on Digital conversion. Roll Microfilm. Roll microfilm is the least expensive microform to produce and duplicate and it is the most widely used. Microfilm comes in rolls 100 feet long (215 feet for thin film). Once filming is completed, adding a new frame (page) somewhere in the middle of the film is difficult.  microform. A generic term for any form, whether film, video tape, paper, or other medium, containing miniaturized or otherwise compressed images which cannot be read without special display devices.  All microform images may be provided as positives or negatives, more often the latter. Three formats are common: microfilm (reels), aperture cards and microfiche (flat sheets). Microform printers can accept positive or negative films and positive or negative images on paper. New machines allow the user to scan a microform image and save it as a digital file-see the section below on Digital conversion. Microfilm and microfiche contain miniaturized images of pages from printed text such as archival documents, newspapers, magazines, journals, and books. These formats are used to preserve fragile materials and to save space in a library. Microfilm is a spool of 16mm or 35 mm film: Microfiche is a card:  Microforms are any forms, either films or paper, containing microreproductions of documents for transmission, storage, reading, and printing. Microform images are commonly reduced to about one twenty-fifth of the original document size. For special purposes, greater optical reductions may be used. Microform printers can accept positive or negative films and positive or negative images on paper. New machines allow the user to scan a microform image and save it as a digital file-see the section below on Digital conversion. Microform is a general term for any material that contains a small image or microreproduction of a document. These document images are usually found on film, however some older formats used cardboard. There are two common film formats: microfilm and microfiche. Microfilm is a roll of film. Microfiche is a flat sheet of film. Since the images are so small, special readers/scanners are used to view the documents
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what is a microform