RE: switch($action) { case "something": ...

I am trying to figure out someone else's example to produce code of my own. In the following code, what is the "createcalendar" in the second line? the filename of the php document itself? what is case? The php documentation is not really helping me. I AM GETTING ERROR of unexpected T variable here. What am I doing wrong? I will provide more information if needed, but I don't know what to provide. switch($action) { case "createcalendar": create_calendar(); break; default: html_header(); entercalendar_form(); html_footer(); break; } thanks-Marlene