Open/closed principle: going further, it's extends, not inherit!

Most developers are trying to introduce more quality, maintainability and extensibility in their code nowadays, but what tools/frameworks/principles can they use to achieve that? SOLID is one of the main principles list people follow, and looking at the O (Open Closed Principle), some people get confused or have different interpretations. In this talk, Thomas is aiming to demonstrate with implementation example and theory what the Open Close principle actually means, and how and why you should use it in your own projects.