Individuals (SOHO) to enterprise businesses.
eFax by j2 Global sends and receives faxes without the use of a dedicated fax machine. Because faxing using eFax is an entirely digital process, subscribers can save on paper, ink, and of course the fax machine itself.
Signing up for eFax simply requires a fax number, which can be pre-existing or reserved by the service. eFax can send documents in PDF, EFX, or TIFF formats, and can automatically attach a cover page (templates included) and digital signature. Because eFax faxes are digital, they are easy to track using one of the eFax apps (web, mobile, or desktop). The apps also offer a standard address book.
Note that the standard eFax service is intended for moderately sized businesses. j2 Global offers a popular enterprise service (the company claims it is used by over half of Fortune 500 companies) designed to manage larger document loads over multiple fax numbers. A Broadcast service (for sending high volumes of faxes) and Developer service (for fax-heavy industries with heavy automation needs) are also offered.
As a bonus, eFax provides subscribers with a large file transfer service similar to that offered by YouSendIt. Otherwise there isn’t much to eFax, which is kind of the point.