How does a fax machine transmits document?
Both the sender and the receiver must have a fax machine. The sender inserts the document into a document feeder and dials the telephone number of the fax machine to which the message is being sent. Once the telephone connection is made, a light-sensitive device scans each page and creates an electric signal corresponding to the light and dark spots on the page. This signal is coded and sent over telephone lines to the receiving fax machine. That machine uses the signal to create an exact duplicate of the original page, and prints it out.
