Stack Overflow
Q&A for professional and enthusiast programmers
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Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Japanese Language
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Board & Card Games
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Role-playing Games
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English Language Learners
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Music: Practice & Theory
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Area 51
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Code Golf
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Electrical Engineering
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Chemistry
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Software Engineering
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Retrocomputing
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Linguistics
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Ask Ubuntu
Q&A for Ubuntu users and developers
Chess
Q&A for serious players and enthusiasts of chess
Mathematics Educators
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Software Recommendations
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Philosophy
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Open Source
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Physics
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Cross Validated
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Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems