what is the $row variable in php? and whats the duty of $row variable in php? : function getCats() {

 global $con;

 $get_cats = "select * from categories";  //select from database
 
 $run_cats = mysqli_query($con, $get_cats);  //
 
while($row_cats = mysqli_fetch_array($run_cats)) {
	
	$cat_id = $row_cats['cat_id'];
	$cat_title = $row_cats['cat_title'];
	
	echo"<li><a href='#'>$cat_title</a></li>";
	
	}
 
}