Some of the date formats in php mainly we used in coding are mentioned below

Assuming today is March 10th, 2012, 5:16:18 pm, and that we are in the
Mountain Standard Time (MST) Time Zone

<?php


$today = date("F j, Y, g:i a");                 // March 10, 2012, 5:16 pm
$today = date("m.d.y");                         // 03.10.12
$today = date("j, n, Y");                       // 10, 3, 2012
$today = date("Ymd");                           // 20120310
$today = date('h-i-s, j-m-y, it is w Day');     // 05-16-18, 10-03-12, 1631 1618 6 Satpm12
$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 17:16:18 MST 2012
$today = date('H:m:s \m \i\s\ \m\o\n\t\h');     // 17:03:18 m is month
$today = date("H:i:s");                         // 17:16:18
$today = date("Y-m-d H:i:s");                   // 2012-03-10 17:16:18 (the MySQL DATETIME format)
?>

Hope this will get you some information on Date formats in php