//Main----------------------------------------------------------------------------- static void Main(string[] args) { //Inheritance and Polymorphism //Instantiate derived class and access its inherited public method derivedClass d = new derivedClass(7, "Smith"); Console.WriteLine(d.Legs); //returns 4 d.Bark(); //returns Woof d.Speak(); Console.WriteLine(derivedClass.Number); //protected members of base class d.SayName(); //Works because derived class SayName method has access to base class' field/var //d.LastName = "Jones"; //error, due to "protected" protection level in base class //Polymorphism Shape c = new Circle(); c.Draw(); //outputs circle Shape r = new Rectangle(); r.Draw(); //outputs rectangle //Abstract class abstractClass v = new abstractCircle(); v.Draw(); //circle //Interface IShape z = new interfaceCircle(); z.Draw(); //Outputs circle drawing ISquash y = new interfaceCircle(); y.Squash(); //Outputs about squashing //Namespaces System.Console.WriteLine("Hello"); //Here, "System" would be required if "using System;" was not called at the start of the file. }