Fax server
A fax server is a system installed in a local area network (LAN) server that allows computer users whose computers are attached to the LAN to send and receive fax messages. Alternatively the term "fax server" is sometimes used to describe a program that enables a computer to send and receive fax messages, set of software running on a server computer which is equipped with one or more fax-capable modems (or dedicated fax boards) attached to telephone lines or, more recently, software modem emulators which use T.38 ("Fax over IP") technology to transmit the signal over an  IP network. Its function is to accept documents from users, convert them into faxes, and transmit them, as well as to receive fax calls and either store the incoming documents or pass them on to users. Users may communicate with the server in several ways, through either a local network or the Internet. In a big organization with heavy fax traffic, the computer hosting the fax server may be dedicated to that function, in which case the computer itself may also be known as a fax server. User interfaces. For outgoing faxes, several methods are available to the user: For  incoming faxes, several user interfaces may be available: Advantages over paper fax machines. Fax servers offer various advantages over traditional fax systems: Public fax services. There are many Internet fax providers operating fax servers as a commercial public service. Subscribers can interact with the servers using methods similar to those available for standard fax servers, and would be assigned a dedicated fax number for as long as they maintain their subscription. Fees are normally charged on a flat monthly rate, with a limit on the number of fax pages sent and/or received. Integrated fax programs. An integrated fax program is  a complete set of faxing software which operates on a single computer which is equipped with a fax-capable modem connected to a telephone line. Its user interfaces may be similar to those used to communicate with fax servers, except that since the entire operation takes place on the user's computer the user may be made more aware of the progress of the transmission. Integrated fax programs are aimed at consumers and small organizations, and may sometimes be bundled with the computer's operating system.