User`s guide

Appendix E: Glossary
188 Pinnacle Systems DekoMOS User’s Guide
interpreter. Graphical user interfaces allow you to enter commands by clicking, with a mouse,
objects that appear on the screen.
Parallel Port
An interface for connecting an external device such as a printer. Most personal computers
have both a parallel port and at least one serial port.
On PCs, the parallel port uses a 25-pin connector (type DB-25) and is used to connect printers,
computers, and other devices that need relatively high bandwidth. It is sometimes called a
Centronics interface after the company that designed the original standard for parallel
communication between a computer and printer. The modern parallel interface is based on a
design by Epson.
Port
(1) An interface on a computer to which you can connect a device. Personal computers have
various types of ports. Internally, there are several ports for connecting disk drives, display
screens, and keyboards. Externally, personal computers have ports for connecting modems,
printers, mice, and other peripheral devices.
Almost all personal computers come with a serial RS-232C port or RS-422 port for
connecting a modem or mouse and a parallel port or USB port for connecting a printer.
(2) In networks, an endpoint to a logical connection; the place, internally, where one computer
listens for information from another computer. The port number identifies what type of port it
is. For example, port 80 is used for HTTP traffic.
(3) To move a program from one type of computer to another. To port an application, you need
to rewrite sections that are machine dependent, and then recompile the program on the new
computer.
Server
A computer, or a software package, that provides a specific kind of service to client software
running on other computers. The term can refer to a particular piece of software, such as a
Web server, or to the machine on which the software is running, e.g. “Our mail server is down
today. That's why e-mail isn't getting out.”
A single server machine can have several different server software packages running on it,
thus providing many different servers to clients on the network. Sometimes server software is
designed so that additional capabilities can be added to the main program by adding small
programs known as surfeits.
USB Port
Universal Serial Bus, an external bus standard that supports data transfer rates of 12 Mbps. A
single USB port can be used to connect up to 127 peripheral devices, such as mice, modems,
and keyboards. USB also supports Plug-and-Play installation and hot plugging.
Starting in 1996, a few computer manufacturers started including USB support in their new
machines. USB is now used widely. It is expected to completely replace serial and parallel
ports.