[Shamun]

Go to admin settings and in the general options area at the very bottom is a checkmark to enable/disable debug mode. Turn that on and whenever you view a page you'll get a pop-up with all available variable names and arrays.

It's formated as {$varName.$arrayName} when you want to access them on a tpl.

So a var with the name of $foo had an array with a var inside with a name of bar then you would use {$foo.bar} in the tpl.



$current_category.categoryid = Only for the current category. Look at the url and you'll see the number for the category.
$current_category.parentid = Only for the parent category. Go up one level and you'll see it.