Code Review
Q&A for peer programmer code reviews
Stack Overflow
Q&A for professional and enthusiast programmers
Software Engineering
Q&A for professionals, academics, and students working within the systems development life cycle
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
Mathematics
Q&A for people studying math at any level and professionals in related fields
Quantum Computing
Q&A for engineers, scientists, programmers, and computing professionals interested in quantum computing
Code Golf
Q&A for programming puzzle enthusiasts and code golfers
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
MathOverflow
Q&A for professional mathematicians
Spanish Language
Q&A for linguists, teachers, students and Spanish language enthusiasts in general wanting to discuss the finer points of the language
Japanese Language
Q&A for students, teachers, and linguists wanting to discuss the finer points of the Japanese language
Physics
Q&A for active researchers, academics and students of physics
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community