P4 may refer to:

Computing

Intel Pentium 4 Pentium 4 is a series of single-core CPUs for desktops, laptops and entry-level servers manufactured by Intel. The processors were shipped from November 20, 2000 until August 8, 2008. The production of Netburst processors was active from 2000 u ...

, a 7th-generation processor design ** The P4 power connector introduced to power it and later CPUs in the ATX12V 1.0 standard * The i486DX (P4) model of the

Intel 80486 The Intel 486, officially named i486 and also known as 80486, is a microprocessor. It is a higher-performance follow-up to the Intel 386. The i486 was introduced in 1989. It represents the fourth generation of binary compatible CPUs following the ...

, a high-performance microprocessor *

P4 (programming language) P4 is a programming language for controlling packet forwarding planes in networking devices, such as routers and switches. In contrast to a general purpose language such as C or Python, P4 is a domain-specific language with a number of constru ...

, for describing packet forwarding * P4, the

Perforce Perforce, legally Perforce Software, Inc., is an American developer of software used for developing and running applications, including version control software, web-based repository management, developer collaboration, application lifecycle mana ...

software command line client

Media

* P4 Radio Hele Norge (PFI), a Norwegian radio company ** Kanal 24 (Kanal 4), which acquired the Norwegian P4 channel from PFI * Sveriges Radio P4, a Swedish radio channel * ''

Persona 4 released outside of Japan as ''Shin Megami Tensei: Persona 4'', is a 2008 role-playing video game by Atlus. It is chronologically the fifth installment in the ''Persona'' series, itself a part of the larger ''Megami Tensei'' franchise, and was ...

'', a 2008 video game * '' Periphery IV: Hail Stan'', 2019 album by American progressive metal band Periphery

Military

* Skaraborg Regiment (armoured), a Swedish army unit whose designation is P 4 * Peugeot P4, a vehicle used by the French Military

Science

* P4 laboratory, a biosafety level 4 facility *

Tetraphosphorus Elemental phosphorus can exist in several allotropes, the most common of which are white and red solids. Solid violet and black allotropes are also known. Gaseous phosphorus exists as diphosphorus and atomic phosphorus. White phosphorus White ...

(P₄), an allotrope of phosphorus * Group p4, the plane symmetry group Wallpaper group p4 *

Progesterone Progesterone (P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the m ...

(Pregn-4-ene-3,20-dione), a steroid hormone * Kerberos, the fourth moon of Pluto * Perfect fourth, an interval in music theory *

Enterobacteria phage P4 ''Enterobacteria phage P4'' (also known as satellite phage P4) is a temperate bacteriophage strain of species ''Escherichia virus P2'' within genus ''Peduovirus'' (formerly ''P2-like viruses'', ''P2virus'', and ''P2likevirus''), subfamily ''Peduo ...

* P4, an EEG electrode site according to the 10-20 system * P4 cell, a stage in the ''Caenorhabditis elegans'' embryonic development * P4 metric - performance metric of the binary classifier.

Roads

* P4 road (Latvia) *

P04 road (Ukraine) road is a state regional road in Ukraine connecting the capital of Ukraine, Kyiv and town Zvenyhorodka in Cherkasy Oblast. It is long. The route starts in Kyiv, goes through Fastiv, Bila Tserkva, Tarashcha and ends in Zvenyhorodka. See also ...

Other uses

* Papyrus 4, a New Testament manuscript *

Trans-Pacific Strategic Economic Partnership The Trans-Pacific Strategic Economic Partnership Agreement (TPSEP), also known as P4, is a trade agreement between four Pacific Rim countries concerning a variety of matters of economic policy. The agreement was signed by Brunei, Chile, Singapore ...

, or P4, a free trade agreement between Brunei, Chile, New Zealand, and Singapore *

Prussian P 4 The Prussian P 4 was a derivative of the P 4.1 (Hanover variant) and the second superheated steam locomotive in the world. Design The engine was based on that of the Class P 4.1 that had Hanomag had produced in large numbers si ...

, German steam locomotive * Protofour, or P4, a set of standards for model railways