Stack Overflow
Q&A for professional and enthusiast programmers
Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Meta Stack Overflow
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Science Fiction & Fantasy
Q&A for science fiction and fantasy enthusiasts
Mathematics
Q&A for people studying math at any level and professionals in related fields
Game Development
Q&A for professional and independent game developers
Server Fault
Q&A for professional system and network administrators
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Photography
Q&A for professional, enthusiast and amateur photographers
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems.
User Experience
Q&A for user experience researchers and experts
Stack Apps
Q&A for apps, scripts, and development with the Stack Exchange API
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
Ask Different
Q&A for power users of Apple hardware and software
German Language & Usage
Q&A for speakers of German wanting to discuss the finer points of the language and translation
