diferencias de las etiquetas <?php ?> y <?=?>

[rodrigo_00]

http://php.net/manual/en/ini.core.php

short_open_tag boolean
... Tells whether the short form (<? ?> ) of PHP's open tag should be allowed....
... Also if disabled, you must use the long form of the PHP open tag (<?php ?> )....

Note: This directive also affects the shorthand <?= , which is identical to <? echo . Use of this shortcut requires short_open_tag to be on.

Saludos

PD: que post tan largo para una pregunta que originalmente era tan simple jaja ^^