Most people who work in office settings have at least a basic familiarity with fax machines. The concept is simple -- the fax machine scans a document, encodes the information and transmits it across the phone line. The fax machine on the other end of the line decodes the signal and prints a facsimile of the document.
Services that allow people to send faxes via e-mail work on the same principle, but a computer and the Internet take the place of a fax machine. These services assign fax numbers to their customers, and they provide a way to send documents without a fax machine.

To send a fax over e-mail:

The sender attaches a file -- like a Microsoft Word file or a scan of a paper document -- to an e-mail message through an e-mail program or a Web interface.
The sender addresses the message to the recipient's fax number. Depending on the service, the sender may also add the name of the faxing service (for example: 18005551234@emailfaxes.com).
The service translates the attachment so that a fax machine can read it.
The service sends the data across the phone line.
The recipient's fax machine decodes the data and prints the fax.
To receive a document from a traditional fax machine:
The sender dials the recipient's fax number.
The fax machine translates and transmits the data.
The service receives the data, translates it into an image file and sends it to the recipient's e-mail address.
The recipient opens the email message and the attachment and views the file.
E-mail fax services are often less expensive and more flexible than purchasing a traditional fax machine and telephone service for it.

 
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