Programmers
Q&A for professional programmers interested in conceptual questions about software development
User Experience
Q&A for user experience researchers and experts
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Ask Different
Q&A for power users of Apple hardware and software
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
Mathematics
Q&A for people studying math at any level and professionals in related fields
Physics
Q&A for active researchers, academics and students of physics
Game Development
Q&A for professional and independent game developers
Meta Stack Overflow
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems.
Server Fault
Q&A for professional system and network administrators
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community
Academia
Q&A for academics and those enrolled in higher education
English Language Learners
Q&A for speakers of other languages learning English
Programming Puzzles & Code Golf
Q&A for programming puzzle enthusiasts and code golfers
Personal Productivity
Q&A for people wanting to improve their personal productivity
The Workplace
Q&A for members of the workforce navigating the professional setting
Writers
Q&A for authors, editors, reviewers, professional writers, and aspiring writers