php - Where does the form submit to if there is no action specified?

Question

Here is the form that is confusing me

<h1>
    Login
</h1>
<form action="" method="post">
    <table align="left" border="0" cellspacing="0" cellpadding="3">
        <tr>
            <td>
                Username:
            </td>
            <td>
                <input type="text" name="user" maxlength="30">
            </td>
        </tr>
        <tr>
            <td>
                Password:
            </td>
            <td>
                <input type="password" name="pass" maxlength="30">
            </td>
        </tr>
        <tr>
            <td colspan="2" align="left">
                <input type="checkbox" name="remember">
                <font size="2">
                    Remember me next time
            </td>
        </tr>
        <tr>
            <td colspan="2" align="right">
                <input type="submit" name="sublogin" value="Login">
            </td>
        </tr>
        <tr>
            <td colspan="2" align="left">
                <a href="register.php">Join</a>
            </td>
        </tr>
    </table>
</form>

I got the code from this tutorial and it works fine but i cant seem to understand where a/the form submit too if no action is present

Answer 1

If action is set to "" or if the action attribute is missing, the form submits to itself. That is, if your script is index.php, your form submits to index.php.