Datatables data from json_encode PHP array

Their documentation ( datatables.net ) regarding this seems to be tucked inside some huge PHP tutorial. The one I found is here: http://datatables.net/development/server-side/php_mysql

All I want to know, is how to make an array, using PHP which will later be hit with json_encode() with static data (no variables) to populate a table which has a few column titles and a few example rows of data. Some of this was taken from the tutorial above.

<?php
    $output = array(
        "sEcho" => intval($_GET['sEcho']), //no idea what this is
        "iTotalRecords" => $iTotal, //probably total records
        "iTotalDisplayRecords" => $iFilteredTotal, //Not sure, records per page?
        "aaData" => array() //setting the data array for the rows
        );
    $output['aaData'][] = //each row here, unsure of format

    //Where do the column titles go, and the format for those?
?>
<script type="text/javascript">
    $(document).ready(function() {

        var aDataSet = <?php echo json_encode($output); ?>

        $('#demo').html( '<table cellpadding="0" cellspacing="0" border="0" class="display" id="example"></table>' );
        $('#example').dataTable( {
            "aaData": aDataSet,
            "aoColumns": aoDataSet //This would be a second json_encode PHP array, set to var aoDataSet
        } ); 
    } );
</script>

Any help would be appreciated.

EDIT: With some help from user2657979's answer, I have the answer to my question now. Below is the answer to populate DataTables title and data from PHP arrays.

<?php
$aoColumnDefs = array(
    array(
        'sTitle'   => 'Column 1',
        'aTargets' => array(0) 
    ),
    array(
        'sTitle'   => 'Column 2',
        'aTargets' => array(1) 
    ),
    array(
        'sTitle'   => 'Column 3',
        'aTargets' => array(2) 
    ),
    array(
        'sTitle'   => 'Column 4',
        'aTargets' => array(3) 
    ),
    array(
        'sTitle'   => 'Column 5',
        'aTargets' => array(4) 
    )
);

$aoRowDefs = array(
    0   =>  array(
        0   =>  "Row 1 data Column 1", 
        1   =>  "Row 1 data Column 2",
        2   =>  "Row 1 data Column 3",
        3   =>  "Row 1 data Column 4",
        4   =>  "Row 1 data Column 5"
        ),
    1   =>  array(
        0   =>  "Row 2 data Column 1",
        1   =>  "Row 2 data Column 2",
        2   =>  "Row 2 data Column 3",
        3   =>  "Row 2 data Column 4",
        4   =>  "Row 2 data Column 5"
        ),
    2   =>  array(
        0   =>  "Row 3 data Column 1",
        1   =>  "Row 3 data Column 2",
        2   =>  "Row 3 data Column 3",
        3   =>  "Row 3 data Column 4",
        4   =>  "Row 3 data Column 5"
        )
    );
?>

<script type="text/javascript">

    var aoRowDefs = <?php echo json_encode($aoRowDefs); ?>

    var aoColumnDefs = <?php echo json_encode($aoColumnDefs); ?>

    $(document).ready(function() {
        $('#demo').html( '<table cellpadding="0" cellspacing="0" border="0" class="display" id="example"></table>' );
        $('#example').dataTable( {
        "aaData": aoRowDefs,
        "aoColumns": aoColumnDefs
        } ); 
    } );
</script>

<div id="demo">
    <div id="example">
    </div>
</div>