1.  Pagination

$display is how many records to show or add per page.
$records are the queries that are in SQL.
$start is where in the database to start running the script.
$rowp is the results of the query.

2. Sorting

case is in other words a condition statement. If the case is last name display last name.
$order_by tells the code what to sort itself by. Much like in SQL it can be by first name, last name, or ascending, descending order.
(echo '<a href="?sort=lname">Last name</a> |';) creates a link to sort by. When that link is clicked the records rearrange themselves accordingly. 

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