Untitled

PHP and mysql not INSERTing
<html>
<head>
<title> Register </title>
</head>
<body>

Thanks for showing interest, please register below.
<br>


<br/>
<form action="register.php" method="POST">
Username: <input type="text" name="username">
<br>

</br>
Password: <input type="password" name="password">
<br>

</br>
Age:      <input type="text" name="age">
<br>

</br>
Car:      <input type="text" name="car">
<br>


<input type="submit" value="register"/>
<input type="reset" value="Reset fields"/>
</form>

<?php

    //db connect
    $host="localhost";
    $dbuser="site1login";
    $dbpass="site1login";
    $dbname="login";
    $tblname="userdata";

    //form post
    $Username=$_POST['username'];
    $Password=$_POST['password'];
    $Age=$_POST['age'];
    $Car=$_POST['car'];
    $con = mysql_connect("$host","$dbuser","$dbpass") or die (mysql_error());

    mysql_select_db($dbname, $con);

    $result = mysql_query("INSERT INTO `userdata` (Username,Password,Age,Car) VALUES ($Username, $Password, $Age, $Car)" or die(mysql_error()));
    echo "Success!";

?>

</body>

</html>

$result = mysql_query("INSERT INTO `userdata` (Username,Password,Age,Car) VALUES
             ($Username, $Password, $Age, $Car)" or die(mysql_error()));
echo "Success!";

$result = mysql_query("INSERT INTO userdata (Username,Password,Age,Car) VALUES
          ('$Username', '$Password', '$Age', '$Car')");

if($result)
{
    echo "Success!";
}
else
{
    die(mysql_error());    // Thanks to Pekka for pointing this out.
}

if($result)
{
    // Successful query execution
}
else
{
    // Some error occured while executing query.
    // Show some useful information using echo/print.
    // Then stop execution after taking other necessary steps
}

$result = mysql_query("INSERT INTO `userdata` (Username,Password,Age,Car)
          VALUES ($Username, $Password, $Age, $Car)" or die(mysql_error()));

$result = mysql_query("INSERT INTO `userdata` (Username,Password,Age,Car)
          VALUES ('$Username', '$Password', '$Age', '$Car')");

if (!$result)
 die("SQL Error: ".mysql_error());

echo "Success";

$result = mysql_query("INSERT INTO `userdata` (Username,Password,Age,Car) VALUES ('$Username', '$Password', $Age, '$Car')") or die(mysql_error();