Assembly Program Of Print a String

Data segment;
  msg db 'hello world','$';
  Data ends;

  Code segment;
  assume cs : Code, ds : Data;
  start:
        mov ax, Data;
        mov ds, ax;

        mov ah, 09h;
        mov dx, offset msg;

        int 21h;

        mov ah, 4ch;
        mov al, 00h;

        int 21h;
  Code ends
  end start;