Fax (short for facsimile), sometimes called telecopying, is the telephonic transmission of scanned printed material (both text and images), normally to a telephone number connected to a printer or other output device. The original document is scanned with a fax machine (or a telecopier), which processes the contents (text or images) as a single fixed graphic image, converting it into a bitmap, and then transmitting it through the telephone system. The receiving fax machine reconverts the coded image, printing a paper copy. Before digital technology became widespread, for many decades, the scanned data was transmitted as analog. Although businesses usually maintain some kind of fax capability, the technology has faced increasing competition from Internet-based alternatives.
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