Stack Overflow
Q&A for professional and enthusiast programmers
Super User
Q&A for computer enthusiasts and power users
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
Ask Ubuntu
Q&A for Ubuntu users and developers
Web Applications
Q&A for power users of web applications
Vi and Vim
Q&A for people using the vi and Vim families of text editors
Software Engineering
Q&A for professionals, academics, and students working within the systems development life cycle
Role-playing Games
Q&A for gamemasters and players of tabletop, paper-and-pencil role-playing games
Reverse Engineering
Q&A for researchers and developers who explore the principles of a system through analysis of its structure, function, and operation
Retrocomputing
Q&A for vintage-computer hobbyists interested in restoring, preserving, and using the classic computer and gaming systems of yesteryear
Raspberry Pi
Q&A for users and developers of hardware and software for Raspberry Pi
Quantum Computing
Q&A for engineers, scientists, programmers, and computing professionals interested in quantum computing
Poker
Q&A for serious players and enthusiasts of poker
Physics
Q&A for active researchers, academics and students of physics
Physical Fitness
Q&A for physical fitness professionals, athletes, trainers, and those providing health-related needs
Open Source
Q&A for people organizing, marketing or licensing open source development projects
Mythology & Folklore
Q&A for enthusiasts and scholars of mythology and folklore
Movies & TV
Q&A for movie and TV enthusiasts
Lifehacks
Q&A for people looking to bypass life's everyday problems with simple tricks
Internet of Things
Q&A for builders and users of networked sensors and control devices in the contexts of smart homes, industry automation, or environmental sensors
Information Security
Q&A for information security professionals
Game Development
Q&A for professional and independent game developers
Freelancing
Q&A for self-employed and freelance workers
DevOps
Q&A for software engineers working on automated testing, continuous delivery, service integration and monitoring, and building SDLC infrastructure
Cryptography
Q&A for software developers, mathematicians and others interested in cryptography
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Network Engineering
Q&A for network engineers
Music Fans
Q&A for music historians, critics, and fans
Medical Sciences
Q&A for professionals in medical and allied health fields, students of those professions, related academics, and others with a sound understanding of medicine and healthcare-related sciences