Stack Overflow
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Open Source
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English Language & Usage
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Game Development
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Vi and Vim
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Aviation
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Code Review
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Science Fiction & Fantasy
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Academia
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The Workplace
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Q&A for computer enthusiasts and power users
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Software Engineering
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Physics
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Arqade
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Mathematics
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German Language
Q&A for speakers of German wanting to discuss the finer points of the language and translation
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Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites