Please explain, it seems it converts decimal to binary but how I don't know..... Code is in description

Question

#include<stdio.h>
#include<conio.h>
void bin(unsigned int n);
void main()
{
bin(7);
printf("\n");
bin(4);
}

void bin(unsigned int n)
{
if(n>1)
bin(n/2);
printf("%d", n%2);
}

Answer 1

void main illegal, oh really! Is that the case?
I am using this app called Decoder, it seems to be using the new C language (at least that's what I think). I wrote this code in that and copied and pasted here.

Answer 2

How to get updated on such things
I mean what sources do you use