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Mathematics
Q&A for people studying math at any level and professionals in related fields
Physics
Q&A for active researchers, academics and students of physics
Mathematica
Q&A for users of Wolfram Mathematica
Philosophy
Q&A for those interested in the study of the fundamental nature of knowledge, reality, and existence
Chemistry
Q&A for scientists, academics, teachers, and students in the field of chemistry
Biology
Q&A for biology researchers, academics, and students
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
German Language
Q&A for speakers of German wanting to discuss the finer points of the language and translation
Area 51
Q&A for proposing new sites in the Stack Exchange network
Psychology & Neuroscience
Q&A for practitioners, researchers, and students in cognitive science, psychology, neuroscience, and psychiatry
History of Science and Mathematics
Q&A for people interested in the history and origins of science and mathematics
Physical Fitness
Q&A for physical fitness professionals, athletes, trainers, and those providing health-related needs
Computational Science
Q&A for scientists using computers to solve scientific problems
Computer Science
Q&A for students, researchers and practitioners of computer science
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Cross Validated
Q&A for people interested in statistics, machine learning, data analysis, data mining, and data visualization
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Ask Different
Q&A for power users of Apple hardware and software
Stack Overflow
Q&A for professional and enthusiast programmers
Artificial Intelligence
Q&A for people interested in conceptual questions about life and challenges in a world where "cognitive" functions can be mimicked in purely digital environment
Bitcoin
Q&A for Bitcoin users, developers, and enthusiasts
Politics
Q&A for people interested in governments, policies, and political processes
Cryptography
Q&A for software developers, mathematicians and others interested in cryptography
Ethereum
Q&A for users of Ethereum, the decentralized application platform and smart contract enabled blockchain
Information Security
Q&A for information security professionals
The Workplace
Q&A for members of the workforce navigating the professional setting
Data Science
Q&A for Data science professionals, Machine Learning specialists, and those interested in learning more about the field
Personal Finance & Money
Q&A for people who want to be financially literate
Software Engineering
Q&A for professionals, academics, and students working within the systems development life cycle
Code Golf
Q&A for programming puzzle enthusiasts and code golfers
Quantitative Finance
Q&A for finance professionals and academics
Christianity
Q&A for committed Christians, experts in Christianity and those interested in learning more
Movies & TV
Q&A for movie and TV enthusiasts
Arqade
Q&A for passionate videogamers on all platforms
Linguistics
Q&A for professional linguists and others with an interest in linguistic research and theory
Travel
Q&A for road warriors and seasoned travelers
Writing
Q&A for the craft of professional writing, including fiction, non-fiction, technical, scholarly, and commercial writing
Academia
Q&A for academics and those enrolled in higher education
Proof Assistants
Q&A for mathematicians and computer scientists who develop and use proof assistants