Print on demand

Print on demand (POD) is a printing technology and business process in which book copies (or other documents) do not print until the company receives an order, allowing prints of singular or small quantities. While other industries established the build to order business model, "print on demand" could only develop after the beginning of digital printing, because it was not economical to print single copies using traditional printing technology such as letterpress and offset printing.

Many traditional small presses have replaced their traditional printing equipment with POD equipment or contract their printing to POD service providers. Many academic publishers, including university presses, use POD services to maintain large backlists (lists of older publications); some use POD for all of their publications. Larger publishers may use POD in special circumstances, such as reprinting older, out of print titles or for test marketing.

Before the introduction of digital printing technology, production of small numbers of publications had many limitations. Large print jobs were not a problem, but small numbers of printed pages were typically during the early 20th century produced using stencils and reproducing on a mimeograph or similar machine. These produced printed pages of inferior quality to a book, cheaply and reasonably fast. By about 1950, were available to make paper master plates for offset duplicating machines. From about 1960 copying onto plain paper became possible for photocopy machines to make multiple good-quality copies of a monochrome original. As technology advanced it became possible to store text in digital form—- paper tape, punched cards readable by digital computer, magnetic mass storage, etc.—- and to print on a teletypewriter, line printer or other computer printer, but the software and hardware to produce original good-quality printed colour text and graphics and to print small jobs fast and cheaply was unavailable.

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