Question

What does it mean?
Having a non-static class which has for example one static method?

Without creating an instance of that class, we can’t use it. But What about its static method?

Answer 1

The static method can be used without the need of instantiating the class. One common case this is used is when the constructor of a class is private and a static method is provided to return instances, like a factory. For example the Create method:

XmlReader reader = XmlReader.Create("test.xml");