PHP array stores multiple values. PHP has several ways to define an array variable.

<?PHP
$week=array(1,2,3,4,5,6,7);  //number array

$week=array("Mon","Tue","Wed","Thr","Fri","Sat","Sun");  //String array

$week=array();
$week[0]=1;
$week[1]=2;
$week[2]=3;
$week[3]=4;
$week[4]=5;
$week[5]=6;
$week[6]=7;
?>

When define an array element value, if the index is not specified, the value will be appended to the last of the array.

<?PHP
$week=array(1,2,3,4,5,6,7);
$week[]=1; //$week[7]=1
?>

Array can be iterated by foreach():

<?PHP
$week=array(1,2,3,4,5,6,7);
foreach($week as $d)
{
   echo "$d, "; //1, 2, 3, 4, 5, 6, 7, 
}
?>

Array can also be iterated by for() loop:

<?PHP
$week=array(1,2,3,4,5,6,7);
for($i=0;$i<count($week);$i++)
{
   echo "$week[$i], "; //1, 2, 3, 4, 5, 6, 7, 
}
?>

Multi dimensional array:

<?PHP
$arr = array(
   array(1,4),
   array(5,8),
   array(9,2)
);
echo "$arr[2][0]";  //9

///////////////////
$arr = array();
$arr[0] = array(1,4);
$arr[1] = array(2,3);
$arr[2] = array(4,2);
echo "$arr[1,1]";  //3

for ($i=0;$i<count($arr);$i++)
{
   echo "$arr[$i][0], "; //1, 2, 4, 
}
?>

PHP associative array stores multiple key value pairs.

<?PHP
	$arr = array("one"=>"Monday","two"=>"Tuesday","three"=>"Wednesday",
	"four"=>"Thursday","five"=>"Friday","six"=>"Saturday","seven"=>"Sunday");
	foreach($arr as $num=>$d)
	{
		echo "$num, $d\n";
	}
?>