Milline väärtus on peidetud SOLID põhimõtetes O tähe taga?

The letter "O" in the SOLID principles stands for the Open/Closed principle. It states that software entities (classes, modules, functions) should be open for extension, but closed for modification.

This means that the behavior of the system can be extended without changing existing code, which reduces the risk of errors and makes maintenance easier.

Example: if you need to add new functionality, it is better to create a new class that implements the required interface, rather than modifying the existing class.