PDA – see Personal Digital Assistant

Peripheral – Any Input/output device belogning to a computer that is not part of the essential computer (ie. CPU, RAM). They are usually situated relatively close to the system and are sometimes even internal devices, examples include: hard drive, CD-ROM, printer and scanner.

Peripheral Component Interconnect (PCI) – A connection architecture that allows the computer to communicate with PCI expansion slots and the devices connected to them.

Personal Digital Assistant (PDA) – A portable hand-held computer with software capable of tracking names, addresses, phone numbers, appointments and other information. The most common PDA available is the PalmPilot by 3Com.

Ping – A network program that sends UDP packets to a host and listens for responses. It is generally used to see if a connection to another computer on the network or Internet is possible.

Plug-ins - Plug-in applications are secondary programs used as part of your Web browser to increase its functionality. They are automatically recognized automatically and integrated into the main HTML file that is being viewed. Examples include: Adobe Acrobat plug-in for viewing .PDF documents, and Macormedia's Flash player. This term is sometimes referred to as a Add In by other software manufacturers.

Point-to-Point-Protocol (PPP) – The method or "rules" used by two computers connected by a serial interface to communicate. The serial connection is usually a phone line connected to a server.

POP3 – see Post Office Protocol

Portrait – A term used to describe a paper's orientation when printing. In this case, the page will be printed with the longer side running vertically.

Post Office Protocol 3– The standard protocol for receiving email. Messages are stored on a server until you download them to your computer for viewing.

PPP – see Point-to-Point-Protocol

Printer - A device that accepts text and graphic output from a computer and transfers the information to paper, usually to standard size sheets of paper.

Properties – A summary description of a file or program. Some programs allow you to customize the properties and thereby alter its functionality.

Protocol – Any standard for the exchange of information, it defines the specific wording and control flow for communications between two or more programs, devices, or systems. Simply put, it describes the rules that a system must follow in order to communicate with another system.

Proxy - A proxy is used for hosts behind firewalls where the firewall host sends an http request to the proxy server that forwards the http to the real web server outside, gathers the response and sends it back to the internal host.