C :

#include<stdio.h>

int main()
{
   printf("Hello World!"); 
  return 0;
}

C++ :

#include<stdio.h>
 
int main()
{
printf("Hello World!"); 
return 0; 
}

Pascal :

begin
  writeln('Hello World!');
end.

Python :

# coding=utf-8
print("Hello World!")