Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems.
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Science Fiction & Fantasy
Q&A for science fiction and fantasy enthusiasts
TeX - LaTeX
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Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
Mathematics
Q&A for people studying math at any level and professionals in related fields
Meta Stack Overflow
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Game Development
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Server Fault
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Academia
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English Language & Usage
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Physics
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Electrical Engineering
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Role-playing Games
Q&A for gamemasters and players of tabletop, paper-and-pencil role-playing games
Geographic Information Systems
Q&A for cartographers, geographers and GIS professionals
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
WordPress Answers
Q&A for WordPress developers and administrators
Cryptography
Q&A for software developers, mathematicians and others interested in cryptography
Raspberry Pi
Q&A for users and developers of hardware and software for Raspberry Pi
Computer Science
Q&A for students, researchers and practitioners of computer science
The Workplace
Q&A for members of the workforce navigating the professional setting