Why is the .ctor() created when I compile C# code into IL?

Question

With this simple C# code, I run csc hello.cs; ildasm /out=hello.txt hello.exe.

class Hello
{
    public static void Main()
    {
        System.         


        

Answer 1

This is covered in section 10.11.4 of the C# language spec

If a class contains no instance constructor declarations, a default instance constructor is automatically provided. That default constructor simply invokes the parameterless constructor of the direct base class

Here Hello has no defined constructor hence the compiler inserts the default do nothing constructor which just calls the base / object version