Education
5,614 pages · most loved first · page 199 of 234· Tonble one of these
The Opera Database
A huge free reference to more than 37,000 operas and 4,000 aria PDFs, plus art songs, zarzuelas and plot synopses for si…
The Opera Game: A Chess Story
An interactive novelization of Paul Morphy's famous Opera Game, retelling a chess match as a story about revolution as y…
The Opportunity Atlas
An interactive map of every US neighborhood showing how children who grew up there fared as adults - incomes, incarcerat…
The Original Affluent Society
A 1979 Fifth Estate piece on hunter-gatherer societies and Marshall Sahlins's argument that early peoples enjoyed leisur…
The OSI Model
A plain-language walkthrough of the seven OSI layers, with the related protocols, services, and key concepts for each la…
The Papal Encyclicals Online
An online library of papal encyclicals, drawn from the Pierian Press collection covering 1740 to 1981, useful for religi…
The Paris Review
The storied literary magazine's site featuring its famous Writers at Work interviews, essays, poetry, and the Daily cult…
The Parthenon 3D
A digital reconstruction of the Parthenon on the Athens Acropolis as it looked in antiquity, with renders of the colossa…
The Partially Examined Life
A philosophy podcast and blog where hosts read a text in advance and discuss it in an unrehearsed but well-informed conv…
The past was not that cute
A thoughtful essay arguing that pretty vintage aesthetics are not history, and that romanticizing the past erases how ha…
The People's Dictionary
A free Swedish-English online dictionary run by KTH and improved by user suggestions, with translations and word forms f…
The Perfect Loaf
A sourdough baking site by Maurizio Leo, offering detailed bread recipes, starter guides, and troubleshooting for home b…
The Philosophers' Magazine
An online philosophy magazine publishing essays, interviews, and commentary that bring academic philosophy to a curious…
The Philosophy Foundation
A UK charity bringing philosophical enquiry to children and communities, with free resources and session plans for discu…
The Phone in Your Hand
A layer-by-layer interactive teardown of a smartphone, peeling back screen, sensors and chips to explain how the most in…
The Photographic Periodic Table
Theodore Gray's periodic table built from thousands of photographs of real element samples, each with stories, data, and…
The Phrase Finder
A reference site tracing the meanings and origins of thousands of English phrases, sayings, and idioms, researched by Ga…
The Phrenology Page
A long-running reference page on the discredited science of phrenology, with history, terminology in many languages and…
The Phrontistery
A compendium of obscure, rare, and forgotten English words organized into themed lists for browsing and vocabulary disco…
The Physics Aviary
A collection of interactive physics simulations, games and tools for exploring mechanics, waves, circuits and more in th…
The Physics Classroom
A free physics course for students and teachers with plain-language tutorials, concept builders, interactive simulations…
The Physics Travel Guide
An expository physics wiki that explains each concept at three levels - intuitive, concrete and abstract - so you can pi…
The Pirate Surgeon's Journal
A guide to 17th and 18th century sea surgery, with pages on the ship environment, tools, procedures and the medicine of…
The Planetary Society
The space advocacy organization co-founded by Carl Sagan, publishing accessible articles, mission guides, and imagery ab…
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