I refer others to these posts constantly; I may as well put them here.
Shell Scripting Basics
- Why is using a shell loop to process text considered bad practice?
- Why does my shell script choke on whitespace or other special characters?
- Why is printf better than echo?
- Why is looping over find's output bad practice?
Also highly recommended:
- Bash Pitfalls
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Vi and Vim
Q&A for people using the vi and Vim families of text editors
Academia
Q&A for academics and those enrolled in higher education
The Workplace
Q&A for members of the workforce navigating the professional setting
Mathematics
Q&A for people studying math at any level and professionals in related fields
Science Fiction & Fantasy
Q&A for science fiction and fantasy enthusiasts
Politics
Q&A for people interested in governments, policies, and political processes
Parenting
Q&A for parents, grandparents, nannies and others with a parenting role
Stack Overflow
Q&A for professional and enthusiast programmers
Ask Different
Q&A for power users of Apple hardware and software
Worldbuilding
Q&A for writers/artists using science, geography and culture to construct imaginary worlds and settings
Computer Science Educators
Q&A for those involved in the field of teaching Computer Science
Interpersonal Skills
Q&A for people looking to improve their interpersonal communication skills
Super User
Q&A for computer enthusiasts and power users
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community
Software Engineering
Q&A for professionals, academics, and students working within the systems development life cycle
Writing
Q&A for the craft of professional writing, including fiction, non-fiction, technical, scholarly, and commercial writing
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Graphic Design
Q&A for Graphic Design professionals, students, and enthusiasts
Personal Finance & Money
Q&A for people who want to be financially literate
Code Review
Q&A for peer programmer code reviews
Computer Science
Q&A for students, researchers and practitioners of computer science
Cryptography
Q&A for software developers, mathematicians and others interested in cryptography
English Language Learners
Q&A for speakers of other languages learning English
Board & Card Games
Q&A for people who like playing board games, designing board games or modifying the rules of existing board games
Movies & TV
Q&A for movie and TV enthusiasts
User Experience
Q&A for user experience researchers and experts
Software Quality Assurance & Testing
Q&A for software quality control experts, automation engineers, and software testers
Mathematics Educators
Q&A for those involved in the field of teaching mathematics
Software Recommendations
Q&A for people seeking specific software recommendations
Arqade
Q&A for passionate videogamers on all platforms
Server Fault
Q&A for system and network administrators
Chess
Q&A for serious players and enthusiasts of chess
Web Applications
Q&A for power users of web applications
Music Fans
Q&A for music historians, critics, and fans
Law
Q&A for legal professionals, students, and others with experience or interest in law
Cross Validated
Q&A for people interested in statistics, machine learning, data analysis, data mining, and data visualization
Information Security
Q&A for information security professionals
Travel
Q&A for road warriors and seasoned travelers
Code Golf
Q&A for programming puzzle enthusiasts and code golfers
Blender
Q&A for people who use Blender to create 3D graphics, animations, or games
Freelancing
Q&A for self-employed and freelance workers
Sound Design
Q&A for sound engineers, producers, editors, and enthusiasts
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Philosophy
Q&A for those interested in the study of the fundamental nature of knowledge, reality, and existence
Hardware Recommendations
Q&A for people seeking specific hardware recommendations
Game Development
Q&A for professional and independent game developers
Linguistics
Q&A for professional linguists and others with an interest in linguistic research and theory
Home Improvement
Q&A for contractors and serious DIYers
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Pets
Q&A for pet owners, caretakers, breeders, veterinarians, and trainers
Retrocomputing
Q&A for vintage-computer hobbyists interested in restoring, preserving, and using the classic computer and gaming systems of yesteryear
Music: Practice & Theory
Q&A for musicians, students, and enthusiasts
Data Science
Q&A for Data science professionals, Machine Learning specialists, and those interested in learning more about the field
Quantum Computing
Q&A for engineers, scientists, programmers, and computing professionals interested in quantum computing
Physical Fitness
Q&A for physical fitness professionals, athletes, trainers, and those providing health-related needs
Bricks
Q&A for LEGO® and building block enthusiasts
Arduino
Q&A for developers of open-source hardware and software that is compatible with Arduino
Astronomy
Q&A for astronomers and astrophysicists
Puzzling
Q&A for those who create, solve, and study puzzles
Bitcoin
Q&A for Bitcoin users, developers, and enthusiasts
Lifehacks
Q&A for people looking to bypass life's everyday problems with simple tricks
History
Q&A for historians and history buffs
Raspberry Pi
Q&A for users and developers of hardware and software for Raspberry Pi
Literature
Q&A for scholars and enthusiasts of literature
Economics
Q&A for those who study, teach, research and apply economics and econometrics
Biology
Q&A for biology researchers, academics, and students
Role-playing Games
Q&A for gamemasters and players of tabletop, paper-and-pencil role-playing games
MathOverflow
Q&A for professional mathematicians
The Great Outdoors
Q&A for people who love being outdoors enjoying nature and wilderness, and learning about the required skills and equipment
Earth Science
Q&A for those interested in the geology, meteorology, oceanography, and environmental sciences
Space Exploration
Q&A for spacecraft operators, scientists, engineers, and enthusiasts
Russian Language
Q&A for students, teachers, and linguists wanting to discuss the finer points of the Russian language
Open Source
Q&A for people organizing, marketing or licensing open source development projects
Buddhism
Q&A for people practicing or interested in Buddhist philosophy, teaching, and practice
Physics
Q&A for active researchers, academics and students of physics
DevOps
Q&A for software engineers working on automated testing, continuous delivery, service integration and monitoring, and building SDLC infrastructure
Motor Vehicle Maintenance & Repair
Q&A for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles
Stack Apps
Q&A for apps, scripts, and development with the Stack Exchange API
Photography
Q&A for professional, enthusiast and amateur photographers
Area 51
Q&A for proposing new sites in the Stack Exchange network