E-fax is on online fax service used by over 11 million customers worldwide. It is the largest digital fax network. It works via email so there is no need for paper, toner or a fax machine. The customer only needs an email account with any server.The service gives you a 30 day free trial and 300 free pages. The customer chooses their own fax number and can add it to their business card. E-fax then sends their faxes via email attachment, and they can receive forward and save faxes within their email also.