Предлагаю ВНИМАТЕЛЬНО почитать мануал.
там ВСЕ написано.
/* Today is March 10th, 2001, 5:16:18 pm */
$today = date("F j, Y, g:i a"); // March 10, 2001, 5:16 pm
$today = date("m.d.y"); // 03.10.01
$today = date("j, n, Y"); // 10, 3, 2001
$today = date("Ymd"); // 20010310
$today = date(\'h-i-s, j-m-y, it is w Day z \'); // 05-16-17, 10-03-01, 1631 1618 6 Fripm01
$today = date(\'\\i\\t \\i\\s \\t\\h\\e jS \\d\\a\\y.\'); // It is the 10th day.
$today = date("D M j G:i:s T Y"); // Sat Mar 10 15:16:08 MST 2001
$today = date(\'H:m:s \\m \\i\\s\\ \\m\\o\\n\\t\\h\'); // 17:03:17 m is month
$today = date("H:i:s"); // 17:16:17