Stack Overflow
Q&A for professional and enthusiast programmers
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Q&A for professional programmers interested in conceptual questions about software development
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Q&A for professional graphic designers and non-designers trying to do their own graphic design
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Stack Exchange Network staging zone, where users come together to build new Q&A sites
Server Fault
Q&A for professional system and network administrators
User Experience
Q&A for user experience researchers and experts
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Q&A for linguists, etymologists, and serious English language enthusiasts
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Q&A for theoretical computer scientists and researchers in related fields
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Q&A for enthusiasts and power users of the Android operating system
Software Quality Assurance & Testing
Q&A for software quality control experts, automation engineers, and software testers
Answers OnStartups
Q&A for entrepreneurs looking to start or run a new business
Personal Productivity
Q&A for people wanting to improve their personal productivity