There are a number of things introduced into PHP with the idea of making things easier for the developer. Short tags is one of those. I’m sure you’ve seen it. Instead of
<?php

to start a PHP block of code, the “short tag” version is
<?

Well, as a short cut… I guess those three characters could add up. There are some downsides, though. The main one being that short tags can be configured differently - and so they may be turned off - on other servers. For all we know, short tags may be removed as an option all together in future versions of PHP.

So I want to encourage you to use the long version <?php in your code. You’ll ensure better portability and future proofing.

Another version of a short tag is shown here:

<?=$x ?>
<?php echo $x ?>

Those two lines are exactly the same if shorts tags is set to on. I’m sure you can see the temptation to use short tags in those situations. It’s quicker and, some would say, easier to write.

Still - especially if you’re distributing code that will end up on a number of different servers - stick to the long version and you’ll be better off.

Switch it off on your production machines (short_open_tag in the ini file) and just pretend it doesn’t exist. You won’t miss it.