Stack Overflow
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Q&A for computer enthusiasts and power users
Game Development
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Mathematics
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Chemistry
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Area 51
Q&A for proposing new sites in the Stack Exchange network
Physics
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Electrical Engineering
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User Experience
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Arqade
Q&A for passionate videogamers on all platforms
Stack Apps
Q&A for apps, scripts, and development with the Stack Exchange API
Ask Different
Q&A for power users of Apple hardware and software
Poker
Q&A for serious players and enthusiasts of poker
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Server Fault
Q&A for system and network administrators
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts