I noticed that get_header() acts differently from include('header.php'). For instance, when using a state variable to tell my navbar which menu item to mark highlighted I have to INCLUDE my header (it's actually my footer that has the navbar but no matter)... because if I just use get-header() it doesn't see the variable.
There must be a difference in when the php is interpretted by the server.
Here's a question: if I php include a file with php... can I then (in the included file) include another file with php... and so on... ? Will the server know to not stop interpretting all of these php tags until it's done them all... and ONLY THEN send it to my browser?