Can includes be done in just regular .htm pages?

[Grump]

If you put this line:

AddType application/x-httpd-php .php .phtml .php3 .html .htm .shtml

into the root .htaccess file it will allow .htm or .html files to be parsed so that includes can be used on them. It may slow your server down, lots of debate on how significant this is. I have used this for years now with no problems or noticeable difference in speeds.