Stack Overflow
Q&A for professional and enthusiast programmers
Super User
Q&A for computer enthusiasts and power users
Code Review
Q&A for peer programmer code reviews
Software Recommendations
Q&A for people seeking specific software recommendations
Ask Ubuntu
Q&A for Ubuntu users and developers
Photography
Q&A for professional, enthusiast and amateur photographers
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Cross Validated
Q&A for people interested in statistics, machine learning, data analysis, data mining, and data visualization
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community
Data Science
Q&A for Data science professionals, Machine Learning specialists, and those interested in learning more about the field
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
The Workplace
Q&A for members of the workforce navigating the professional setting
Academia
Q&A for academics and those enrolled in higher education
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Mathematics
Q&A for people studying math at any level and professionals in related fields
Server Fault
Q&A for system and network administrators
Geographic Information Systems
Q&A for cartographers, geographers and GIS professionals