Fax or facsimile transmission is a new system of sending information on paper through telephone line. It is different from other communication system like telex and electronic mail. All types of documents, either printed or handwritten, line diagrams or photographs can be sent or received using the fax machine.
A modern fax machine takes less than 30 seconds to send a written paper. In the beginning, fax machines were of the analog type but now digital machines are in common use.
A fax machine scans the document by light and the image is changed into electrical signals by photocells. The message travels through the telephone line and is received by the fax machine at the other end. After decoding, the machine produces a printed copy of the original document.
The coding and decoding system of the entire fax machine in the world is the same. So you can send the document from your fax machine to any other fax machine. Every fax machine has a number like a telephone, which has to be dialed before sending a message.