How do I include PHP into an HTML file?

Good day all,

I'm a complete newbie to PHP. I mostly do HTML, but right now I am working on a project that requires the use of both. Is it possible to include PHP into a HTML document and have it still run at PHP?

What I mean is, I know that you can have HTML in a .php file, but can you have PHP in a .html file? If not what is the best solution to this problem. I would like to have them both co-exist with each other so that I can get the best of both worlds.

Mostly what I would be including in the end result is <?php echo> where the PHP will echo information from another file into the present file, if that makes sense.

Thanks in advance

 

I think you will be ok just to embed the code into the html document.

 

Just rename file php and start the doc with the <?php tag and use ?> for end and <? start of php throughout the doc. for ex
<?php
sum variables or includes
?>
sum html here for header
<? if (sumthin =sumthin) {?>
sum reg html here
<?}?>
some more html here etc...
<? echo "whohoo"; /*add newlines if needed*/
?>