Internet fax uses the Internet to receive and send faxes.

Internet faxing, "e-Fax" or "online faxing" is a general term which refers to sending a document facsimile using the Internet, rather than using only phone networks (traditional faxing) with a fax machine.

Depending on the specific method/implementation (see below), advantages of using the Internet can include

Note that depending on which method is used, suitable equipment and/or the use of a gateway is required (see below).

Fax has no technical advantage over sending information over the Internet, using technologies such as email, scanner, and graphics file formats (however, it is extremely simple to use: put the documents to be faxed in a hopper, dial a phone number, and press a button). Fax continues to be used over the telephone network at locations without computer and Internet facilities; and sometimes a fax of a document with a person's handwritten signature is a requirement for legal reasons. Computer fax over the Internet allows fax communication without an actual fax machine at either or both ends.