How to Define PHP Tags?

Canonical PHP tags

This style is most universally effective and popular PHP tag style. It looks like this:

<?php ?>

It is safe to use this style as some of the other style of php tags may be phased out in the future.

Short-open (SGML-style) tags

This is a shortest option of php tag style. It looks like this:

<? ?>

You must do one of two things to enable PHP to recognize the tags:
· Choose the --enable-short-tags configuration option when you’re building PHP.
· Set the short_open_tag setting in your php.ini file to on. This option must be disabled to parse XML with PHP because the same syntax is used for XML tags.

ASP-style tags

This Style of tags is just like Microsoft’s ASP Style tags. It looks like this:

<% %>

To use ASP style tags you should change the php.ini configuration

HTML script style tags

HTML script style tags is looks like this:

<SCRIPT LANGUAGE=”PHP”> </SCRIPT>

When using this kind of style be careful if you are using lots of javascript then the close tags are fatally ambiguous.