If you want your file to be interpreted as php then your file must start and end with <?php and ?> and everything outside of that is ignored by the php parser.
<?php
php code..php code..?>
hellow..//normal test but ignred by php parser
Three types of tag are available in php
1.normal tag(<?php ?>)
2.short echo tag(<?= ?>)
3.short tag(<? ?>)
short
tag are bydefault available but can be disabled by short_open_tag = Off
and also disabled bydefault if php will built with
--disabe--short--tags()
As short tag can be disabled so only use the normal and short echo tag.
If your file only have php code then do not use closing tag.
<?php
but if you are embedding php with html then enclose php code with opening and closing tag.
<html>
<head>
</head>
<body>
<?php
?>
</body>
</html>
If you want to just print single text or something ,you should use shorthand version .<?= $var ?>
But if you want to process something, you should use normal tag.
<?php
?>
If you embedded php with html and single line, do not need to use semicolon
<html>
<head>
<body>
<?= $var ?>
</body>
</head>
</html>
but if you have multiple line, then use semicolon.
<?php
?>