Question

I do not know what a method without an access identifier is called. In this code block, I am referring to the void updateNumTo5 method.

private int num = 0;

#region public methods
public int Get7()
{
    return 7;
}
#endregion

#region private methods
private int get6()
{
    return 6;
}
#endregion

#region Unknown name
void updateNumTo5()
{
   num = 5;
}
#endregion

Answer 1

The default access modifier (not identifier) is private for methods. So this:

private void Foo()
{
}

is equivalent to

void Foo()
{
}

The general rule is that the default access modifier is always the most restricted you could specify it as. So for example, non-nested types are internal by default, whereas nested types are private by default.