$foo[0][0] = "zenia";       $foo[0][1] = "markownikowa"; $foo[0][2] = "10";
$foo[1][0] = "marek";       $foo[1][1] = "butalski";     $foo[1][2] = "20";
$foo[2][0] = "teresa";      $foo[2][1] = "parufkowa";    $foo[2][2] = "90";
$foo[3][0] = "bogumila";    $foo[3][1] = "pierdowa";     $foo[3][2] = "40";
$foo[4][0] = "genowefa";    $foo[4][1] = "tempawa";      $foo[4][2] = "50";

First -- let's sort these by the [][1] column... the result should be:

marek           brutalski       20
zenia           markownikowa    10
teresa          parufkowa       90
bogumila        pierdawa        40
genowefa        tempawa         50

sorting by the [][2] column should give us:

zenia           markownikowa    10
marek           brutalski       20
bogumila        pierdawa        40
genowefa        tempawa         50
teresa          parufkowa       90