Difference Between Design Patterns and Design Principles

Design Patterns:

What are they?: Design patterns are reusable solutions to common problems encountered in software design. They are templates for how to solve a particular problem in different contexts. Patterns provide a structured approach to solve problems that developers frequently encounter.
Purpose: Provide a tried-and-tested approach to solving specific issues, ensuring consistency and maintainability in the codebase.
Examples:
- Creational Patterns (Factory, Singleton, Builder)
- Structural Patterns (Adapter, Facade, Composite)
- Behavioral Patterns (Observer, Strategy, Command)

What are they?: Design principles are general guidelines that help developers create better, maintainable, and scalable software. They focus on writing code that is easy to maintain, extend, and understand, rather than solving specific design issues.
Purpose: Guide developers to write more robust and flexible software by applying general best practices.
Examples:
- SOLID Principles (Single Responsibility, Open-Closed, Liskov Substitution, Interface Segregation, Dependency Inversion)
- DRY (Don’t Repeat Yourself)
- KISS (Keep It Simple, Stupid)
- YAGNI (You Ain’t Gonna Need It)

Aspect	Design Pattern	Design Principles
Definition	Solution templates for specific problems	Guidelines for writing clean, maintainable code
Scope	Solves common software design issues	General best practices and rules to follow
Purpose	To provide a well-known structure to solve a design issue	To promote good coding practices and code maintainability
Examples	Singleton, Factory, Observer, Strategy	SOLID, DRY, KISS, YAGNI
Usage	Implemented as part of code architecture	Used as rules for the design and architecture of the system