In a console program in C #, where is the main class defined?

I'm doing my first console program in C #, just to do some testing.

I have two classes: HelloConsole.MainClass and HelloConsole.Calc .

I have the following code:

using System;

// Aprendendo o alias de namespace

using C = System.Console;

namespace HelloConsole
{
    class MainClass
    {
        public static void Main (string[] args)
        {
            Calc calc = new Calc (3);

            /** 
             * Agora já sei que WriteLine aceita múltiplos parâmetros
             * Tipo o Python
             * */

            C.WriteLine ("O valor é {0}", calc.value);

            C.WriteLine ("Soma de {0}", calc.sum (3));

            C.WriteLine ("Multiplo de 3 é {0}", calc.mul(3));

            Calc calc_2 = new Calc (1, 2, 3, 4, 5);

            C.WriteLine("Valores da instância diferente {0}", calc_2.value);

            C.WriteLine ("Valores de multiplicação é {0}", calc_2.mul(5));



        }
    }
}

This program works perfectly. And I understood that everything that is put inside the static method Main is executed on the console. But I still do not understand where the compiler "knows" which is MainClass which is the main class.

Is this defined somewhere, or does the C # compiler understand that it is the main class because of the name MainClass ?

Is it possible to define another main class?

Is it possible to have more than one main class?

Note : I'm using Linux and compiling for Monodevelop.