How It Works
The code in Main() creates and uses an instance of the MyClass class defined in MyClass.cs. Instantiating this class must be performed using a nondefault constructor because the default constructor of MyClass is private:
private MyClass() : this("Default Name")
{
}

Using this("Default Name") ensures that Name gets a value if this constructor is ever called, which is possible if this class is used to derive a new class. This is necessary because not assigning a value to the Name field could be a source of errors later.

I don't understand, how to call a private constructor if deriving a new class?