fax back

Recipient-controlled information delivery system in which documents stored in a computer (which is equipped with a fax modem or board, and the supporting software) can be 'downloaded' via a fax machine. The recipient dials the sender's number from his or her fax machine, chooses various options in response to voice prompts from the sender's computer, and presses the fax 'start key' to receive the document. In this process all telephone charges are borne by the recipient. Also called fax on demand.