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+#+TITLE: SOLID Principles
+#+OPTIONS: num:nil tags:t toc:t
+#+DATE: <2025-10-18 Sat 19:14> 
+#+FILETAGS: :learning:notes:
+
+The SOLID principles are five design guidelines for writing maintainable, flexible, and scalable object-oriented code. Here's a quick summary:
+
+1. Single Responsibility Principle (SRP): A class should have only one reason to change, meaning it should have a single responsibility or purpose.
+
+2. Open/Closed Principle (OCP): Classes should be open for extension (e.g., adding new functionality) but closed for modification (no need to change existing code).
+
+3. Liskov Substitution Principle (LSP): Subclasses should be substitutable for their base classes without breaking the program's behavior.
+
+4. Interface Segregation Principle (ISP): Clients should not be forced to depend on interfaces they don't use, favoring specific, small interfaces over large, general ones.
+
+5. Dependency Inversion Principle (DIP): High-level modules should not depend on low-level modules; both should depend on abstractions (e.g., interfaces), and abstractions should not depend on details.
+
+These principles promote cleaner, more modular, and testable code.
+