A single bit that is added to a byte of memory in order to check for errors. A byte is composed of 8 bits. Counting the parity bit, a byte is actually composed of 9 bits. Sometimes there is more than one parity bit per byte.
PCI (Peripheral Component Interconnect)
PCI slots connect 32-bit and 64-bit PCI expansion cards to the motherboard. PCI cards send and receive data at speeds of 33Mhz for 32-bit cards and 66Mhz for 64-bit cards.
PCMCIA (Personal Computer Memory Card International Association)
The PCMCIA is responsible for the development of the credit card size PC expansion cards. These cards are used to provide additional memory, network connections, additional drives, and other things for notebook computers. To install a PCMCIA card you simply plug it into a PCMCIA slot located on the computer, normally without even rebooting. To uninstall a PCMCIA card you just unplug it.
PDA (Personal Digital Assistant)
A PDA is a small handheld computer that uses a special pen for inputting data. These small computers, while not as powerful as most standard computers, have most of the basic functions of a regular computer. Many PDAs also allow access to the Internet and can send and receive faxes, email, and even telephone calls. Also known as "palm", "handheld", and "pocket" computers.
PnP (Plug and Play)
PnP refers to a computer having the ability of automatically configuring device settings for a component without the user having to make any manual adjustments. A computer without a PnP operating system has to be configured manually with the BIOS setup program and/or by setting jumpers located on the device and/or motherboard. Most all versions of Windows are PnP. Most all of today's hardware is PnP also.
POST (Power On Self Test)
A computer goes through POST each time it is booted before loading Windows or any other operating system. POST is a test run by the BIOS. It is the first thing a computer does when you turn it on. It checks the memory, connected devices, expansion cards, and other items. It then compares the results with previously stored information on the CMOS chip.
PROM (Programmable Read Only Memory)
PROM can only be programmed one time and can never be erased. PROM is programmed with a special PROM burner, (also known as a PROM programmer). Unlike ROM that comes preprogrammed, PROM is completely blank when manufactured.