JavaScript Function Call

<!DOCTYPE html>
<html>
<body>

<h1>JavaScript Functions</h1>

<script>
const student = {
  fullName: function() {
    return this.firstName + " " + this.lastName;
  }
}
const first = {
  firstName:'Ahmed',
  lastName:'Mohamed'
}
document.write(student.fullName.call(first));
</script>

</body>
</html>