Software Design

• Contain Changes
• Re-usability
• Design and Development Principles
• SOLID - Object Oriented Design Principle
• Single Responsibility: a class should have only a single responsibility
• Open-Closed: “ be open for extension, closed for modification.”
• Liskov substitution: objects should be replaceable, design by contract
• Interface segregation: many client-specific interfaces are better than one general-purpose interface
• Dependency inversion: Depend upon Abstractions. Do not depend upon concretions
• DRY - Don't Repeat Yourself
• KISS - Keep it simple, stupid
• If it ain't broke, don't fix it
• GRASP - OO Design.