E-mail Validation

The function below checks if the content has the general syntax of an email.
 
This means that the input data must contain an @ sign and at least one dot (.). Also, the @ must not be the first character of the email address, and the last dot must be present after the @ sign, and minimum 2 characters before the end:

<html>
<head>
<title>JavaScript Validations</title>
<script>
function validateForm()
{
var x=document.forms["Form1"]["email"].value;
var atpos=x.indexOf("@");
var dotpos=x.lastIndexOf(".");
if (atpos<1 || dotpos<atpos+2 || dotpos+2>=x.length)
  {
  alert("Not a valid e-mail address");
  return false;
  }
}
</script>
</head>
<body>
<form name="Form1" action="second.php" onsubmit="return validateForm()" 
method="post">
  name:
  <input type="text" name="email">
  <input type="submit" value="Submit">
</form>
</body>
</html>