Fax July 1996. A major breakthrough in the development of the modern facsimile system was the result of digital technology, where the analog signal from scanners was digitized and then compressed, resulting in the ability to transmit high rates of data across standard phone lines. The first digital fax machine was the Dacom Rapidfax first sold in late 1960s, which incorporated digital data compression technology developed by Lockheed for transmission of images from satellites. Group 3 and 4 faxes are digital formats, and take advantage of digital compression methods to greatly reduce transmission times. Fax Over IP (FoIP) can transmit and
Internet fax Not all fax equipment claiming T.38 compliance works reliably. In particular communicating with older fax machines is problematic. As with regular faxes, only one fax can be sent or received at a time. While the needs of computer-to-fax communications are well covered, the simplicity of quickly faxing a handwritten document combined with the advantages of email are not. "iFax" (T.37) was designed for fax machines to directly communicate via email. Faxes are sent as email attachments in a TIFF-F format. A new fax machine (supporting iFax/T.37) is required, as well as a known email address for the sending and receiving