Group Standards

The widespread use of fax in business is a more recent phenomenon, and its growth parallels that of the computer for much the same underlying reason. Desktop computers did not take off until the industry found a standard to follow—the IBM computer. Similarly, the explosive growth of fax began only after the CCITT adopted standards for the transmission of facsimile data.


The original system, now termed Group 1, was based on analog technology and used frequency shift keying, much as 300 baud modems do, to transmit a page of information in six minutes. Group 2 improved upon that analog technology and doubled the speed of transmission, up to three minutes per page.

Group 3

The big break with the past was the CCITT's adoption ...

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