Communication
Articles about communication systems, signals and exchange of information.
Post town
Post town (United Kingdom postal addressing)
Postage stamp
Postal code
Postal code (postcode, ZIP code)
Postal codes in Taiwan
Postal Index Number
Postal Index Number (PIN) — India's six-digit postal code system
Postcard
Postcard: history, design, and uses
Postcodes in Australia
Power line communication
Power-line communication (PLC) — transmitting data over electrical wiring
Power-line communication (PLC) transmits digital data over existing AC or DC electrical wiring for applications from smart meters to home networking and industrial control.
Prank phone call
Prediction
Prediction: concepts, methods, history, and practical limits
Preposition
Presentation
Pretty Good Privacy
Pretty Good Privacy (PGP): cryptography, history and uses
Product cipher
Product cipher: structure, types, and cryptographic role
Promotion
Promotion (marketing and communication): methods, history, and uses
Pronunciation
Pronunciation: how words are spoken and what shapes their sound
Propaganda
Proposal
Proto-Indo-European language
Proto-Indo-European language (PIE)
Proto-World language
Proto-World language (Proto‑Human)
Public
Public (communication, public relations, and related fields)
Public speaking
Public speaking: purpose, structure, history and practical techniques
Punctuation
Punctuation: marks, functions, history and common rules
Purchase order
Purchase order: definition, components, process, and practical uses
Q.E.D.
Q.E.D.: meaning, history, and use in mathematics and logic
Quassel
Quassel — distributed, Qt-based IRC client
Quechua
Quechua (Runa Simi): Overview, history, and linguistic features
Question mark
Question mark (punctuation)
Queue
Quipu
Quipu (khipu): Andean knotted-string recording systems
Quotation mark
Radio
Radio (wireless communication and broadcasting)
Radio is the transmission and reception of information by electromagnetic waves. It enables broadcasting, two-way communication, navigation and remote control across many frequency
Radio frequency
Radio frequency: overview, propagation, bands, history and applications
Railway Gazette International
Railway Gazette International — global business journal for the rail industry
Railway semaphore signal
Railway signal
Railway signal: function, types, history and modern systems
Rajasthani language
Reading
Real Time Streaming Protocol
Rebus
Receipt
Receipt: proof of a transaction or delivery
Received Pronunciation
Receiver
Recognition signal
Red box
Red ribbon
Redundancy
Redundancy (information, computing, and engineering)
Reflection
Reflection (wave phenomena)