анонимная функция

js/script.js

var fun1 = function() {
document.write('Hello World!<br />');
}
var fun2 = function fact(n) {
if(n>1) {
return n * fact(n-1);
}
else {
return 1;
}
}

var fun1 = function() {
 document.write('Hello World!
');
}

var fun2 = function fact(n) {
 if(n>1) {
  return n * fact(n-1);
 }
 else {
  return 1;
 }
}

index.html

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>New Page</title>
<script src="js/script.js"></script>
</head>
<body>
<script>
fun1();
document.write('factorial of number 5 = ' + fun2(5));
</script>
</body>
</html>

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>New Page</title>
<script src="js/script.js"></script>
</head>
<body>
<script>
fun1();
document.write('factorial of number 5 = ' + fun2(5));
</script>
</body>
</html>