• PABX Private Automatic Branch EXchange
• PAD Packet Assembler and Disassembler
• PADA Packet Assembler/DisAssembler
• PAHI Public Access Internet Host
• PAIS Public Access Internet Site
• PAL Programmable Array Logic / Phase Alternating Line / Paradox Application Language
• PAP Printer Access Protocol
• PAR Positive Acknowledgment with Retransmission
• PARC Palo Alto Research Center
• PAX Private Automatic EXchange
• PBX Public Branch EXchange
• PC Personal Computer / Popup Context
• PCAMI PC Assets Manager Institute
• PCCA Portable Computer and Communications Association
• PCD Photo Compact Disk
• PCI Protocol Control Information / Peripheral Component Interconnect
• PCL Printer Control Language
• PCM Pulse Code Modulation
• PCMCIA Personal Computer Memory Card International Association
• PCS Personal Communication Services / Personal Conferencing Specification
• PCWG Personal Conferencing WorkGroup
• PD Public Domain
• PDC Primary Domain Controller
• PDF Portable Document Format
• PDIAL Public Dialup Internet Access List
• PDL Page Description Language
• PDN Public Data Network
• PDO Portable Distributed Objects
• PDP Parallel Distributed Processes
• PDS Processor Direct Slot / Personal Display System
• PDU Protocol Data Unit
• PEM Privacy-Enhanced Mail
• PEP Packetized Ensemble Protocol / Packet Exchange Protocol
• PET Personal Electronic Transactor
• PFB Printer Font Binary
• PFM Printer Font Metrics
• PGA Pin Grid Array / Professional Graphics Adapter / Programmable Gate Array
• PGP Pretty Good Privacy
• PI Popup ID
• PIC Programmable Interrupt Controller
• PIF Program Information File
• PIM Personal Information Manager
• PIN Processor Independent Network
• PINE Pine Is Not Elm
• PING Packet InterNet Gopher
• PIO Program's Input/Output
• PK Phil Katz
• PL/1 Programming Language 1
• PL/M Programming Language for Microcomputers
• PLA Programmable Logic Array
• PLE Public Local Exchange
• PLP Presentation Level Protocol
• PM Presentation Manager
• PMJI Pardon Me for Jumping In
• PMS Pantone Matching System
• PMT Photo Multiplier Tube
• PnP Plug 'n' Play
• POP Post Office Protocol / Point Of Presence
• POSIX Portable Operating System Interface for UNIX
• POST Power On Self Test
• POTS Plain Old Telephone System / Plain Old Telephone Service
• PPC Power PC
• PPD Printer Page Description
• PPN Project-Programmer Number
• PPP Point-to-Point Protocol
• PPS Pulses Per Second
• PRAM Parameter Random Access Memory
• PREP Power PC REference Platform
• PRI Primary Rate Interface
• PROFS PRofessional OFfice System
• PROM Programmable Read-Only Memory
• PSC Personal Super Computer
• PSN Packet Switch Node
• PSP Program Segment Prefixes / Presentation Services Process
• PSPDN Packet Switched Public Data Network
• PSRAM Pseudo Static Random Access Memory
• PSTN Public Switched Telephone Network
• PTP Point To Point
• PUC Public Utility Commission
• PVC Private Virtual Circuit / Permanent Virtual Circuit
• pwd print working directory
• PWM Pulse Width Modulator