Mathematics
Q&A for people studying math at any level and professionals in related fields
Philosophy
Q&A for those interested in the study of the fundamental nature of knowledge, reality, and existence
MathOverflow
Q&A for professional mathematicians
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
Music: Practice & Theory
Q&A for musicians, students, and enthusiasts
Physics
Q&A for active researchers, academics and students of physics
Information Security
Q&A for information security professionals
Cryptography
Q&A for software developers, mathematicians and others interested in cryptography
The Workplace
Q&A for members of the workforce navigating the professional setting
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
Academia
Q&A for academics and those enrolled in higher education
Cross Validated
Q&A for people interested in statistics, machine learning, data analysis, data mining, and data visualization
Mathematics Educators
Q&A for those involved in the field of teaching mathematics