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Stack Overflow
Q&A for professional and enthusiast programmers
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Q&A for physical fitness professionals, athletes, trainers, and those providing health-related needs
Ask Different
Q&A for power users of Apple hardware and software
Super User
Q&A for computer enthusiasts and power users
Server Fault
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Bicycles
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Area 51
Q&A for proposing new sites in the Stack Exchange network
Home Improvement
Q&A for contractors and serious DIYers
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Q&A for information security professionals
Photography
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Q&A for the craft of professional writing, including fiction, non-fiction, technical, scholarly, and commercial writing
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Q&A for power users of web applications
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Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
Personal Finance & Money
Q&A for people who want to be financially literate
Ask Ubuntu
Q&A for Ubuntu users and developers
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites