There are three ways of receiving faxesinto your personal computer:
Option 1 - Using a fax modem and fax software
Using fax viewer software.
Inbound faxes are normally delivered to you by email, with the fax attached as a file. The file format of the attachment will usually be TIF, but some providers will give you the option of receiving it as PDF, JPG, or other formats.
Other providers (usually providers of free services) may require a proprietary viewer. This means that you can only view their faxes through their software, which you install on your computer, and which will sometimes include forms of advertising.
Inbound internet faxes are received at the internet fax providers' servers on regular phone lines, then forwarded to you by email. This means that there are two points where security compromises are introduced by the service:
1. On the internet fax provider's fax server - There is no solution to overcome compromise number one. You either trust the provider not to abuse your faxes or you don't.