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Spanish Language & Usage
Q&A for students, teachers, and linguists wanting to discuss the finer points of the Spanish language
Meta Stack Overflow
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Physics
Q&A for active researchers, academics and students of physics
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community
Mathematics
Q&A for people studying math at any level and professionals in related fields
Science Fiction & Fantasy
Q&A for science fiction and fantasy enthusiasts
User Experience
Q&A for user experience researchers and experts
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Game Development
Q&A for professional and independent game developers
Home Improvement
Q&A for contractors and serious DIYers
Web Applications
Q&A for power users of web applications
Cognitive Sciences
Q&A for practitioners, researchers, and students in cognitive science, psychology, neuroscience, and psychiatry
Writers
Q&A for authors, editors, reviewers, professional writers, and aspiring writers
Japanese Language & Usage
Q&A for students, teachers, and linguists wanting to discuss the finer points of the Japanese language
The Workplace
Q&A for members of the workforce navigating the professional setting