PP, pp or Pp may refer to:
Arts and entertainment
- Pianissimo, a music term meaning very quiet, from musical dynamics
- Production code for the 1967–1968 Doctor Who serial The Enemy of the World
- Police Procedural – a subgenre of procedural drama and detective fiction
- Peppa Pig, a British preschool animated television series
Businesses and organisations
Political parties
- Patriotic Party (Guatemala)
- People's Party (Spain) (Partido Popular)
- Pirate Party (Global)
- Progressistas (Brazil) (Progressistas)
- Progressive Party (Iceland)
- People's Partnership (Trinidad and Tobago)
- We Continue the Change (Bulgaria) ("Prodalzhavame promyanata")
Other businesses and organizations
- Pancasila Youth (Pemuda Pancasila), an Indonesian paramilitary organization
- PediaPress, a German software company
- Planned Parenthood, a reproductive health organization
- Philipp Plein, logo
- PayPal, an online payments company
Religion
- pp, Papa Pontifex, post-nominal used by popes
Science, technology, and mathematics
Biology and medicine
- Vitamin PP or nicotinamide
- Paliperidone palmitate, an antipsychotic medication
- Pancreatic polypeptide, a polypeptide secreted by PP cells
- PP cell or pancreatic polypeptide cell
- pro parte, abbreviated p.p., for a type of synonymy in taxonomy
Computing
- PP (complexity), a probabilistic polynomial time complexity class
- PP-format (Post Processing Format), a file format for meteorological data
- PP X.400, an e-mail protocol
- Plug and play (P&P), a property of a peripheral device
- Microsoft PowerPoint, a presentation program
Mathematics
- P–P plot, a probability plot, in statistics
- Percentage point, in business writing and statistics
- Process performance index (Pp)
- Presque partout (almost everywhere), in measure theory and analysis (is always lower case – 'pp'; in English 'ae' is often used instead.)
Other uses in science and technology
- Paris Principles (cataloging), a theoretical foundation for the creation of bibliographical cataloging rules for libraries
- Walther PP, a pistol
- Length between perpendiculars ("pp" or "p/p"), the length of a ship
- Peak to peak (p–p) amplitude of a signal
- Polypropylene, a common plastic polymer
- Proton–proton chain, in nuclear physics and astronomy
Other uses
- p.p., Per procurationem, when signing on behalf of another
- pp, pages (of a book), an example of the convention of doubling the letters in the acronym to indicate plural words, see Acronym and initialism § Representing plurals and possessives
- Percy Pig, a British brand of pig-shaped fruit-flavoured confectionery products
- Peso Pluma, musician
- Pierre Poilievre, Conservative politician in Canada.
- PinkPantheress, singer