What does DRY mean?
DRY stands for Don't Repeat Yourself.
Principle Definition
DRY stands for 'Don't Repeat Yourself' and is a software development principle that emphasizes reducing repetitive patterns and duplicated code in favor of modular and referable code.
Origin
Coined by Andy Hunt and Dave Thomas in 'The Pragmatic Programmer', DRY aims to ensure that each piece of knowledge has a single, unambiguous representation within a system.
Importance
Writing DRY code is essential for maintainability, scalability, and to avoid the opposite, WET code ('Write Everything Twice').
Rule of Three
A good general rule for DRY code is the 'Rule of Three', which suggests abstracting code into a reusable unit the third time a certain pattern is encountered.