All articles starting with P
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Present perfect
The present perfect (have/has + past participle) is a tense-aspect form linking a past event to the present, distinct from the simple past in relevance, adverb compatibility, and British versus American usage.
Present serviceability index
The present serviceability index (PSI) is a pavement quality measure on a scale of 0 to 5, developed at the AASHO Road Test in 1958 to 1960.
Present tense
Present tense: the grammatical category locating an event at the moment of utterance, also covering habitual, generic, and futurate uses; contrasted with past and future tense and with tenseless languages like Mandarin Chinese.
Present value
Present value, also called present discounted value, is the value today of a future amount of money, found by discounting it at a rate reflecting the time value of money.
Presentation
A presentation is a talk or demonstration that conveys information from a speaker to an audience, such as a lecture or business pitch, often supported by visual aids like slides.
Presentation attack detection
Presentation attack detection, also called liveness detection, is a biometric security method that distinguishes a live person from spoofing artifacts like printed photos or masks.
Presentation layer
The presentation layer, also known as OSI layer 6 or the syntax layer, is the OSI model layer that gives applications a common data format, handling translation, encryption, and compression.
Presentation of Colours
Presentation of Colours: the formal ceremony of consecrating and handing over new regimental flags (King's and Regimental Colours) to a military unit, with old colours trooped and laid up; practiced across Britain, Canada, India, and Malaysia.
Presentation of Jesus
The Presentation of Jesus, also known as Candlemas, is the event in Luke 2:22–40 where Mary and Joseph present the forty-day-old Jesus at the Jerusalem Temple, commemorated on February 2.
Presentation of Mary
The Presentation of Mary, also called the Entrance of the Theotokos, is a Christian feast on 21 November commemorating the child Mary being dedicated to God in the Jerusalem Temple.
Presentation of the Kojiki
The Presentation of the Kojiki (古事記献上) was the submission of the Kojiki chronicle to Empress Genmei in 712, compiled by Ō no Yasumaro in three volumes.
Presentation program
A presentation program is software for creating and delivering visual slides combining text, images, charts, and video, dominated by Microsoft PowerPoint, released in 1987 and acquired by Microsoft that year.
Presents from My Aunts in Pakistan
"Presents from My Aunts in Pakistan" is an autobiographical free verse poem by the Pakistani-British poet Moniza Alvi about gifts from her aunts and a divided identity.
Prešeren Award
The Prešeren Award (Slovene: Prešernova nagrada) is the highest state recognition of Slovenia for achievement in the arts, given for lifetime work and presented each year on Prešeren Day, 7 February.
Preservation and digitization of 78 rpm records
Preservation and digitization of 78 rpm records covers the care, storage, playback, and digital transfer of brittle shellac discs that dominated recorded sound from 1898 to the late 1950s.
Preservation and restoration of railway vehicles
Preservation and restoration of railway vehicles is the practice of keeping historic trains and carriages, balancing operational use against static display under the Riga Charter.
Preservation and restoration of small-town opera houses
The preservation and restoration of small-town opera houses is the movement to save 19th- and early-20th-century mixed-use theater buildings, revived by community campaigns since the 1970s.
Preservation in situ of waterlogged archaeological sites
Preservation in situ of waterlogged archaeological sites means leaving organic remains like wood buried in oxygen-poor waterlogged ground, the first option under the 1992 Valletta Convention.
Preservation of private railroad cars
Preservation of private railroad cars is the practice of saving, restoring, and operating privately owned passenger railcars called "private varnish", many restored vintage Pullman cars attached to Amtrak trains.
Preservation rhinoplasty
Preservation rhinoplasty is a surgical technique for nasal hump correction that lowers the dorsum by removing septal cartilage and mobilizing the bony pyramid while keeping the dorsal roof intact.
Preservative
A preservative is a substance added to food, cosmetics, and other products to prevent deterioration by inhibiting microbes, regulated under laws such as the EU cosmetics Annex V list.
Preserved British Rail diesel locomotives
Preserved British Rail diesel locomotives are more than 250 former BR main-line diesels kept on heritage railways, in museums, and on the national network by preservation groups.
Preserved Food
Preserved food: treated to resist spoilage via drying, salting, fermentation, canning (Appert, 1795 prize), refrigeration, freeze-drying, and irradiation; water activity 0.85 pathogen cutoff.
Preserved manual switchboards and exchange museums
Preserved manual switchboards and exchange museums are surviving cord boards and exchange buildings that keep manual telephony, in which operators connected calls by plugging cords, as working artifacts.
Preserved railway carriages and heritage rolling stock
Preserved railway carriages and heritage rolling stock are historic coaches, brake vehicles, and wagons restored and operated on heritage railways and in museums, cataloged by the RCTS.
Preset (company)
Preset, Inc. is a San Mateo, California company founded in 2019 by Apache Superset creator Maxime Beauchemin that offers managed commercial hosting of the Apache Superset BI platform.
Presheaf with transfers
A presheaf with transfers is a contravariant additive functor from smooth schemes with finite correspondences to abelian groups, used by Voevodsky to build motivic cohomology.
Presheath (plasma physics)
The presheath is the quasineutral transition layer of a plasma boundary that accelerates ions from near-thermal energies to the ion sound speed at the edge of the Debye sheath.
Presidencies and provinces of British India
Presidencies and provinces of British India: the directly ruled divisions of the Raj, beginning with Bengal, Madras, and Bombay presidencies and later tiered provinces under Governors, Lieutenant Governors, and Chief Commissioners until 1947.
Presidency College, Chennai
Presidency College, Chennai: government autonomous arts and science college founded 1840, named so in 1855, 'Mother of Madras University', Marina campus by Robert Fellowes Chisholm, NIRF 15 (2025).