Fax technology was designed to send and receive a facsimile (photocopy) of a
document quickly across long distances. The ability to manipulate the received
document defeats the purpose of the facsimile concept, since a manipulated
document is no longer a facsimile of the original.
The facsimile communication protocol does not transmit and receive text. This
protocol is based on the transmission of a graphic image. A Fax document is
composed of scan line information at a resolution of approximately 200 dots per
inch. Thus, the data sent via a Fax machine/modem contains no
computer-readable text -- it's only a graphic image of the original document.
A character recognition application is necessary to translate the graphic image
into text, which a computer can edit.
However, when communicating with a second AppleFax Modem, the AppleFax Modem
has the ability to transmit and receive Macintosh disk files at Fax speeds.