Templates are normal php files, with the expectation that you will do mostly or all display code in it.

No smarties or large templating system is required. They have lots of parsing overhead, give few benefits, and lots of headaches. PHP *is* a templating language !

An array of variables is built up ( $r ) and renderTemplate($r,"templateName") is called.
Templates are searched for down through the CLASS_DIRS folders. The variables from $r are exported into the template file's variable space.

Objekts specify a displayTpl, summarizeTpl and can also specify an editTpl, errorTpl and insertTpl if they need to customize. Trace your inheritance up to find out which template your class is specifying. Usually Objekt is the parent class. edit, error and insert all use the same Objekt-edit.tpl and pass in a variable $mode. Its basically the same except the title changes.

Some php pages in shared-www also use templates to allow the site to customize and arrange as it pleases.