Replacing Javascript with PHP to write HTML

I've got a situation that I need to fix, but I don't know how and I don't
know what I'm looking for is called. I was hoping someone here can help.

Currently, I have a site that is basically set up like this:

HEADER
MENU MAIN CONTENT
FOOTER

The header, menu, and footer are the same on all pages, and the "main
content" is different for each page. Currently I do not use style sheets,
and all of the HTML for all elements of each page is on the pages - except
for the menu. When I set up the pages years ago, I anticipated the menu
changing periodically, so instead of having the menu hard-coded into each
page, I used Javascript to write the menu in, like this:

<p><SCRIPT LANGUAGE="JavaScript" SRC="menu.js"></SCRIPT>

The script uses "document.writeln" to just write the HTML of the menu (text
& links). Needless to say, this is a bad idea. So I was wondering if there
was a way to use PHP to write the menu into each page instead of using
Javascript? And if I'm "linking" to code for the menu, I thought I might as
well do the same for the header and footer, so that if any of those elements
change I can just change the files containing the code for the header and
footer so I don't have to update each page when there is a change.

Furthermore, it seems to me that using style sheets to accomplish this would
be a much better idea, but from the examples I've seen style sheets don't
cover quite what I'm looking to do. Of course, I could be wrong.

How can I use PHP to write content into a file similar to "document.writeln"
for Javascript?

Many thanks to anyone who can assist!

In article <vn4n08h742o5cb.DeleteThis@corp.supernews.com>, JJ wrote:
 >
 > How can I use PHP to write content into a file similar to "document.writeln"
 > for Javascript?
 >
 > Many thanks to anyone who can assist!
 >
 >

something like:

good idea to keep the various include files outside the web tree and each
include file can have html code of its own and other include file if necessary

/// code for index.php
<?php
include ("metainfo.php");
include ("headerinfo.php");

?>

some html code

<?php

include ("menuarray.php");

// a section to draw content from a databse or other text file

?>

some more html code

<?php

include ("footer.php");

?>


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