how to store variable values over multiple page loads

Question

I'm making a php script that stores 3 arrays: $images, $urls, $titles based on the input data of the form within the php file.

I want to print the values of these arrays in the first part of the page and then to pre-fill the form's input fields with the value of the arrays. Also when a user modifies an input field and clicks on "Save" the page should reload with the modfied version.

My problem is that on each call of the php file in a browser the value of the variables gets deleted. Is there a way to store the values of the array so that the form always gets pre-filled with the last saved values?

<?php
//save the arrays with the form data
$images = array($_POST["i0"],$_POST["i1"],$_POST["i2"],$_POST["i3"]);
$urls = array($_POST["u0"],$_POST["u1"],$_POST["u2"],$_POST["u3"]);
$titles = array($_POST["t0"],$_POST["t1"],$_POST["t2"],$_POST["t3"]);
//print the arrays
print_r($images);
print_r($urls);
print_r($titles);
//create the form and populate it
echo "<p><form method='post' action='".$_SERVER['PHP_SELF']."';";
$x = 0;
while ($x <= 3) {
   echo"<div>
            <input name='i".$x."' type='text' value='".$images[$x]."'>
            <input name='u".$x."' type='text' value='".$urls[$x]."'>
            <input name='t".$x."' type='text' value='".$titles[$x]."'>";
       $x++;
}
?>
<br>
<input type="submit" name="sumbit" value="Save"><br>
</form>

Answer 1

Store the variables in a PHP session.

session_start();
$_SESSION['images'] = $images;

Then on next (or any other) page, you can retrieve the values as:

session_start();
$images = $_SESSION['images'];

Answer 2

Changing the scope of the variables to a larger scope, might do the trick. Also, check if you have a post request before updating the values.

<?php
    if(sizeof($_POST) >0)
    {
      //UPDATE VALUES
    }
?>