Server Fault
Q&A for professional system and network administrators
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Q&A for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Photography
Q&A for professional, enthusiast and amateur photographers
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
Cryptography
Q&A for software developers, mathematicians and others interested in cryptography
Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems.
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Bicycles
Q&A for people who build and repair bicycles, people who train cycling, or commute on bicycles
Stack Apps
Q&A for apps, scripts, and development with the Stack Exchange API
WordPress Answers
Q&A for WordPress developers and administrators
Mathematics
Q&A for people studying math at any level and professionals in related fields
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community
Physical Fitness
Q&A for physical fitness professionals, athletes, trainers, and those providing health-related needs
Reverse Engineering
Q&A for researchers and developers who explore the principles of a system through analysis of its structure, function, and operation
Parenting
Q&A for parents, grandparents, nannies and others with a parenting role
The Workplace
Q&A for members of the workforce navigating the professional setting
Musical Practice & Performance
Q&A for musicians, students, and enthusiasts