Entries starting with P
- P-valueA p-value measures how incompatible observed data are with a specified statistical model, usually one that assumes no real effect.
- Pakistan: Geography, History, Culture and Key FactsPakistan is a South Asian nation of about 240 million people, home to K2, the Indus Valley civilization, and a nuclear-armed military.
- Palau: Geography, History, Culture and Key FactsPalau is a western Pacific island nation famed for the UNESCO-listed Rock Islands, exceptional coral reef biodiversity, and pioneering ocean conservation policy.
- Palestine: Geography, History and Political StatusPalestine refers to the West Bank and Gaza Strip, a Palestinian territory in the Middle East whose statehood and borders remain internationally disputed.
- Panama: Geography, History, Culture and Key FactsPanama is a narrow Central American nation joining North and South America, home to the canal linking the Atlantic and Pacific.
- Papua New Guinea: Geography, History, Culture and Key FactsPapua New Guinea is a Pacific island nation of extraordinary linguistic and cultural diversity, occupying the eastern half of New Guinea and its surrounding islands.
- Paraguay: Geography, History, Culture and Key FactsParaguay is a landlocked South American country known for its Spanish-Guarani bilingual culture and the massive Itaipu hydroelectric dam.
- Paris: History, Geography, Culture and Key FactsParis is the French capital on the Seine, home to the UNESCO-listed riverbanks and the Eiffel Tower.
- Percentage pointA percentage point is the simple difference between two percentages: a rate rising from 10% to 12% has risen by 2 percentage points.
- Perth: History, the Swan Bells and Key Facts About Western Australia’s CapitalPerth is Western Australia's capital, founded in 1829, one of the world's most isolated major cities.
- Peru: Geography, History, Culture and Key FactsPeru is a South American country encompassing Pacific coastline, the Andes Mountains, and Amazon rainforest, and home to the ancient Inca capital of Machu Picchu.
- pHpH measures how acidic or basic a water based solution is, on a scale where 7 is neutral, lower is acidic and higher is basic.
- Philippines: Geography, History, Culture and Key FactsThe Philippines is a Southeast Asian archipelago nation of thousands of islands shaped by Malay, Spanish, and American influences.
- Phnom Penh: Geography, History, Culture and Key FactsPhnom Penh is Cambodia's capital, a riverside city centered on the Royal Palace and shaped by the Khmer Rouge era and its aftermath.
- PhonemeA phoneme is the smallest unit of sound that can change the meaning of a word in a particular language.
- PhotosynthesisPhotosynthesis is how plants, algae and some bacteria use sunlight to turn carbon dioxide and water into sugars, releasing oxygen.
- Plate tectonicsPlate tectonics is the theory that Earth's outer shell is broken into slabs that move, building mountains and causing earthquakes at their edges.
- Poland: Geography, History, Culture and Key FactsPoland is a Central European nation on the Baltic Sea known for its medieval history, EU and NATO membership, and cultural heritage.
- Portugal: Geography, History, Culture and Key FactsPortugal is a Western European country on the Atlantic coast of the Iberian Peninsula, known for its Age of Discovery history and cities like Lisbon and Porto.
- Postal votingPostal voting lets a registered voter mark a ballot at home and return it by mail instead of visiting a polling station.
- Prague: History, Geography, Culture and Key FactsPrague is the capital of the Czech Republic, a medieval city shaped by Charles IV, famed for Charles Bridge and Prague Castle.
- Pretoria: History, the Union Buildings and Key Facts About South Africa’s Administrative CapitalPretoria is South Africa's administrative capital, founded in 1855 and home to the Union Buildings seat of government.
- Primary aldosteronismPrimary aldosteronism is a disorder in which the adrenal glands make too much aldosterone, which raises blood pressure.
- Primary sourceA primary source is firsthand evidence from the time of an event, such as a letter, photograph, register or eyewitness account.
- Prime numberA prime number is a whole number greater than 1 whose only positive divisors are 1 and itself, such as 2, 3, 5 and 7.
- PrognosisA prognosis is a medically informed estimate of how a condition is likely to develop, and how likely recovery is.
- Progression-free survivalProgression-free survival is the time from randomization in a trial until a patient disease objectively worsens or they die, whichever comes first.