Fax Site using the Courier satellite. Radio fax is still in limited use today for transmitting weather charts and information to ships at sea. Also, it is also widely used within the medical field to transmit confidential patient information. In 1964, Xerox Corporation introduced (and patented) what many consider to be the first commercialized version of the modern fax machine, under the name (LDX) or Long Distance Xerography. This model was superseded two years later with a unit that would truly set the standard for fax machines for years to come. Up until this point facsimile machines were very expensive and
Fax 33.6 kbit/s. As well as specifying the resolution (and allowable physical size of the image being faxed), the ITU-T T.4 recommendation specifies two compression methods for decreasing the amount of data that needs to be transmitted between the fax machines to transfer the image. The two methods defined in T.4 are: An additional method is specified in T.6: Later, other compression techniques were added as options to ITU-T recommendation T.30, such as the more efficient JBIG (T.82, T.85) for bi-level content, and JPEG (T.81), T.43, MRC (T.44), and T.45 for grayscale, palette, and colour content. Fax machines can negotiate at