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Published directory entries matching your search.
SAT Slayer is a free SAT question bank with over 3,000 real questions covering Reading & Writing and Math. It offers custom practice tests, practice by skill, progress tracking, and mistake review, with no ads, paywall, or account required.
CelesTrak is a 501(c)(3) non-profit that provides orbital data and related resources to the space community. Its site offers NORAD GP element sets, a satellite catalog, conjunction reports, GPS data and space weather data. It notes that 5-digit catalog numbers ran out on 2026-07-11, so newly cataloged objects with 6-digit numbers lack GP data in TLE format.
GeoGrid is a daily trivia game built around a 3×3 grid in which rows and columns each represent a geography category and players name a place fitting both. World mode uses countries and States mode uses U.S. states. Confirmed answers are scored by popularity, with lower scores better, and an Unlimited mode offers randomly generated grids.
An archive of Creative Commons-licensed copies of college textbooks from a textbook publisher, downloaded at the end of 2012 and repackaged for use outside the publisher's website. The books are released under a Creative Commons by-nc-sa 3.0 license; updates from original authors are not expected on the site.
Academic Torrents is a BitTorrent-based distributed system for sharing large research datasets, operated as a product of the Institute for Reproducible Research, a U.S. 501(c)3 nonprofit. It is intended to let researchers replicate and distribute data without the high costs of commercial hosting providers. The site states it makes over 419.44TB of research data available.
The Online Books Page lists over 3 million free books available on the Web, organized by authors, titles, subjects and serials. Its features include exhibits on women writers, banned books and prize-winning books online. It is edited by John Mark Ockerbloom.
VulkanGuide is a work-in-progress guide to the Vulkan graphics API that focuses on dynamic rendering as a base for game engine code. It uses C++20 and Vulkan 1.3, covers initialization, compute shaders, mesh drawing, textures and GLTF scene loading, and targets readers who already know 3D graphics basics. An older version covers Vulkan 1.1.
Codewars is a coding practice website for all programming levels, offering small coding exercises called kata in over 55 programming languages. Users can solve kata in the browser with instant feedback, earn ranks and honor, and participate in a community of over 3 million developers. The platform also allows users to create their own kata and compare solutions with others.
A Byte of Python is a free book that teaches programming using Python. It serves as a tutorial or guide to the language for a beginner audience. The book teaches Python 3, and references to Python 2 are included only for historical context and understanding legacy code.
PassMedicine provides free UCAT revision with over 3,000 practice questions covering Verbal Reasoning, Quantitative Reasoning, Decision Making and Situational Judgement. The interface is designed to mirror the real exam, and users can compare their scores with others and discuss individual questions. A six-month subscription option is listed as free.
An artificial life simulation tool built on a specialized 2D particle engine in CUDA for soft bodies and fluid-like media. Simulated bodies are networks of particles that can be given higher-level functions, such as sensors, muscles and neural networks, and act as digital organisms in a common environment. The software is open-source under the BSD-3-Clause license.
Mahatma Gandhi Central University is a central university in Motihari, Bihar, established by the Central Universities (Amendment) Act 2014 and functional since 3 February 2016. The site presents university administrators, notifications, office orders and news.
The New Mexico Institute of Mining and Technology, known as New Mexico Tech, is devoted to education and research with no artificial distinction between pure and applied research. It offers undergraduate and graduate programs in fields including biology, engineering, computer science and physics, and is test optional with a 3.0 GPA or higher.
The University of Portsmouth is a public university in the United Kingdom with campuses in Portsmouth and London. It offers career-focused undergraduate and postgraduate degree programs, including a unique Connected Degrees option that is the only 3-year undergraduate course with an optional 4th-year placement in the UK. The university ranks in the top 3 modern UK universities for research power and the top 450 globally. It hosts undergraduate and postgraduate open days and supports student work placements.
Canterbury Christ Church University is a higher education institution based in Kent, United Kingdom. It offers undergraduate, postgraduate, apprenticeship and short courses designed to meet real-world needs. The university provides up to £15,000 in scholarships and bursaries subject to eligibility, runs a Sports Scholar Programme, and offers virtual campus tours. It is ranked 2nd in the UK for graduate employment among 111 higher education institutions with 3,000 or more graduates, and top 10 in the UK for teaching quality and student experience. It led a study on the benefits of weekly isometric exercise for blood pressure.
Harvard University is an institution devoted to excellence in teaching, learning, and research, with a mission to develop leaders who make a difference globally. It maintains a global community with work across all seven continents, more than 20 international locations, 26.3 million learners enrolled in Harvard Online courses, and provides instruction in 80+ languages.
The Chomsky Index is a minimalist open-source program that indexes the content of Noam Chomsky. It is available for Windows, macOS, and Ubuntu, and supports normal, separate, and nearby search queries for indexed content. Users can install pre-built executables for their system or build from source using Python 3.7. The project is released under the GPL-3.0 license.
SearchifyX is a fast flashcard searcher tool and the predecessor to Searchify. It acts as a webscraper for Quizlet, Quizizz, and Brainly, letting users query questions from these sites and sort results by similarity to the input query. The tool includes a screen OCR scanner, customizable global hotkeys, and stealth features to prevent websites from detecting window focus changes, and is available as both a GUI application and CLI tool for Linux, Mac OS, and Windows. It was created strictly for educational purposes to demonstrate asynchronous webscraping in Python, requiring Python 3.8 dependencies and Tesseract for OCR functionality.
PyGlossary is a tool for converting dictionary files, also known as glossaries. Its primary purpose is to enable use of offline glossaries in any open source dictionary on any operating system or device. It supports numerous formats, including StarDict, Dictd, Babylon BGL, Kobo, and others. The project provides interfaces such as GTK, Tkinter, command line, Android Termux, and web. It is licensed under GPL-3.0.
Graded is a free, open-source grade tracking application built with the Flutter framework. It allows users to track and manage school grades, with features including automatic average calculation across terms, customizable grading systems, subject management with coefficients, grade export, and Google account backup. It supports Android and iOS, offers light and dark interface modes, and is available in English, French and German under the GPL-3.0 license.
arTIfiCE is a jailbreak for TI CE calculators that restores the ability to run assembly programs and games. arTIfiCE v3 supports only CE OS v5.8.5, while v2 supports CE OS versions up to v5.8.4. Supported models include the TI-83 Premium CE (Edition Python), TI-84 Plus CE (Python), TI-84 Plus CE-T (Python Edition), and TI-82 Advanced Edition Python for OS v5.6.3 to v5.6.6. Installation varies by model and OS version: v3 requires the Inequalz app and transfer of an installer program and AppVar file, while older OS versions use a single program transfer. The AsmHook2 app installed by v3 persists through reboots and RAM resets, only needing a single launch after a RAM reset without a computer.
The Free Learning List is a free, ranked, and categorized directory of free educational resources from the internet. It is provided as a free service by The School of Thought International, a 501(c)(3) nonprofit that creates Creative Commons critical thinking resources. The directory includes YouTube channels, podcasts, eBooks, courses, subreddits, and materials focused on effective thinking, languages, programming, and books, with all content available free to access under Creative Commons licenses.
SurvivalManual is an open source Android application that provides offline access to survival guidance. Its content is curated from the public domain US Army Survival Field Manual FM 3-05.70 (FM 21-76), and the app is designed to remain fully functional without internet connectivity for use during emergencies. The project's content list is curated in a public wiki, and contributions to the project are welcome.
Project Alveus Sanctuary is a 501(c)(3) nonprofit organization operating as a wildlife sanctuary and virtual education center. It provides permanent homes for non-releasable animal ambassadors, streams their journeys 24/7 on Twitch, and produces educational content to foster public appreciation for the animals and their wild counterparts. Its affiliated Alveus Research & Recovery Institute runs conservation breeding programs to support at-risk species.
