Stack Overflow
Q&A for professional and enthusiast programmers
Cross Validated
Q&A for people interested in statistics, machine learning, data analysis, data mining, and data visualization
Mathematics
Q&A for people studying math at any level and professionals in related fields
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Web Applications
Q&A for power users of web applications
Economics
Q&A for those who study, teach, research and apply economics and econometrics
Puzzling
Q&A for those who create, solve, and study puzzles
Code Review
Q&A for peer programmer code reviews
Computer Science
Q&A for students, researchers and practitioners of computer science
Super User
Q&A for computer enthusiasts and power users
Software Engineering
Q&A for professionals, academics, and students working within the systems development life cycle
Signal Processing
Q&A for practitioners of the art and science of signal, image and video processing
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Ask Different
Q&A for power users of Apple hardware and software
Data Science
Q&A for Data science professionals, Machine Learning specialists, and those interested in learning more about the field
Artificial Intelligence
Q&A for people interested in conceptual questions about life and challenges in a world where "cognitive" functions can be mimicked in purely digital environment
Personal Finance & Money
Q&A for people who want to be financially literate
English Language Learners
Q&A for speakers of other languages learning English
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Academia
Q&A for academics and those enrolled in higher education
The Workplace
Q&A for members of the workforce navigating the professional setting