Editing Glossary

; Class 1 : Fax Protocol defined by T.31 standard. Class 1 provides a low-level interface between HylaFAX and the fax modem, where HylaFAX is responsible for issuing modem commands during fax transmission. 

; Class 1.0 : Extension of Class 1 that adds V.34 (SuperG3) high-speed fax capability.

; Class 2 : Implementation of Class 2 by Rockwell. Offical spec for class 2, as defined by T.32 standard, is known as Class 2.0.

; Class 2.0 : Offical spec for class 2 faxing as defined in T.32. With class 2 faxing the fax modem controls the sending or reception of the document. This is in contrast to class 1 where HylaFAX has direct control over the transmission. As class 2 faxing relies heavily upon the fax modem your performance will vary greatly based on the modem manufacturer.

; Class 2.1 : Extension of Class 2.0 that adds V.34 (SuperG3) high-speed fax capability.

; DCE : This is Data Circuit-terminating Equipment, which is any device which connects a computer or terminal (DTE) to a data communications network. In the case of fax, this could be a fax modem or other fax device.

; Group 3 : This is a standard for facsimile communications over analog telephone lines originally approved by the CCITT in its T.4 and T.30 recommendations in 1980. This standard is supported by almost all of the current install base of fax machines and fax devices and is continuing to be updated.

; Handshake : An exchange of electronic signals preceding a communication between two facsimile machines to determine the proper connection for transmission.

; ISDN : This is the Integrated Services Digital Network which is an industry standard public digital telephone network. This network is being implemented in the United States and in other countries worldwide as an advanced alternative to the analog telephone network or PSTN (see PSTN).

; ITU : This is the International Telecommunications Union, which has been the parent body of the CCITT. As of 1993, all the former CCITT telecommunications standards activities will be handled by the ITU Telecommunications Standardization Sector (ITU-T).

; PSTN : This is the Public Switched Telephone Network (PSTN) which supports analog voice and fax calls. 

; T.30 : This is the portion of the ITU-T Group 3 facsimile standard which specifies the protocol through which fax devices can exchange information about their supported characteristics and manage the fax session.

; T.38 : This is the ITU-T recommendation which defines a real time method for fax over IP networks.

; V.34 : This is the ITU-T recommendation describing an advanced modulation method which can be used to transmit data at rates of up to 33.6 kilobits per seconds over analog telephone lines (the PSTN).