Why not a syntax parsing error occurs in PHP?

In PHP, why does </SCRIPT> not show a parse error?

In PHP, why does </SCRIPT> not produce syntax parsing errors?

As a mainstream website construction language, PHP has many traps and requires the programmer's idea.

In the PHP script, if you write the following code:

<? Php </SCRIPT>?>

This PHP script does not prompt any errors, but directly outputs "?> ". This is incredible, so let's write the following code:

<? Php </div>?>

This time the parsing error is prompted, parse error: syntax error, unexpected '<' in...

Why does the first </SCRIPT> prompt no error?

At this time, we need to carefully read the relevant PHP manual there.
Are various ways of starting a block of PHP code:

You can use four different start and end tags in PHP. Two of them, <? PHP?> And <script language = "php"> </SCRIPT> are always available. The other two are short tag and asp style tag, which can be opened or closed in the PHP. ini configuration file. Although some people think that short tag and asp style tag are very convenient, but the portability is poor, it is generally not recommended.

That is, PHP has four tags, and <SCRIPT> is one of them, and? PHP?> Same, always available. The other two must be opened in the configuration file.

1. <? ...?> (Open through short_open_tag in the configuration file)
2. <? PHP...?>
3. <Script language = "php">... </SCRIPT>
4. <%... %> (ASP style label, which is not used in version 5.3.0)