Physics
Q&A for active researchers, academics and students of physics
Server Fault
Q&A for system and network administrators
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
Stack Overflow
Q&A for professional and enthusiast programmers
Mathematics
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Computational Science
Q&A for scientists using computers to solve scientific problems
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Philosophy
Q&A for those interested in the study of the fundamental nature of knowledge, reality, and existence
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
Network Engineering
Q&A for network engineers
Information Security
Q&A for information security professionals
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community
History of Science and Mathematics
Q&A for people interested in the history and origins of science and mathematics
Computer Science
Q&A for students, researchers and practitioners of computer science