Stack Overflow
Q&A for professional and enthusiast programmers
Super User
Q&A for computer enthusiasts and power users
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
DevOps
Q&A for software engineers working on automated testing, continuous delivery, service integration and monitoring, and building SDLC infrastructure
Meta Stack Exchange
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Home Improvement
Q&A for contractors and serious DIYers
Data Science
Q&A for Data science professionals, Machine Learning specialists, and those interested in learning more about the field
Physics
Q&A for active researchers, academics and students of physics
Information Security
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Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
Arqade
Q&A for passionate videogamers on all platforms
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Software Engineering
Q&A for professionals, academics, and students working within the systems development life cycle
Motor Vehicle Maintenance & Repair
Q&A for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles
User Experience
Q&A for user experience researchers and experts
Server Fault
Q&A for system and network administrators
Web Applications
Q&A for power users of web applications
Cross Validated
Q&A for people interested in statistics, machine learning, data analysis, data mining, and data visualization
Open Data
Q&A for developers and researchers interested in open data