Sony
Notebook U
s
er Guide
Glossary
141
PBX
A PBX (Private Branch Exchange) is a private telephone network within an enterprise. Under
this system, the calls between the enterprise members are local and the phone numbers are
made up of 3 or 4 digits. Companies generally choose this phone system for internal
communication because it is less expensive than the regular network. The users can still
share a number of outside lines for making calls external to the PBX.
PC Card
A PCMCIA card. The term PC Card is more widely used than PCMCIA. See PCMCIA.
PCMCIA
PCMCIA (Personal Computer Memory Card International Association) is the name of the
group that produced the specification for the credit card-sized plug-in boards for laptop
computers. The cards used to be called PCMCIA cards, but as this was rather
unpronounceable, these cards are now termed PC cards. An example of a PC card is a credit
card-sized modem.
Pixel
A pixel (Picture Element) is a part of your screen. Your screen is made up of thousands of
pixels, enabling you to see colours and pictures on it. The more pixels, the higher the
resolution and the better the image quality.
Processor
The processor is the brains of the computer; it processes the instructions of your system’s
programs. The processor is also known as the CPU or microprocessor and can be found on
the motherboard (see this word) of your computer.
PS/2
A type of mouse or keyboard port.
PSTN
PSTN (Public Switched Telephone Network) refers to the plain old telephone service, the
national telecommunication networks implementing voice transmission by using analog
signals.
Term
Definition