     _list_sort: (a, b) ->
         # ordering operator, such that some entries are in front
         ord = (el) -> switch el
-            when "Tutorial" then -1
-            when "Intro"    then -2
+            when "Intro"    then -3
+            when "Tutorial" then -2
+            when "Help"     then -1
             else 0
         return ord(a) - ord(b) || a > b
 
     fill_list: (list, entries) ->
+        # the three lists are the levels in the tree of documents. they change dynamically.
+        # there is also a mutually recursive logic, to expand sublevels iff there is just one entry (saves stupid clicks)
+        # fill_list call -> calls select_lvl1/2 -> which in turn calls fill_list again.
         list.empty()
         if entries?
             keys = _.keys(entries).sort(@_list_sort)

        @scroll_visible(@lvl2, t)

    select_doc: (t) ->
        @set_active(@document, t)
        @title = t.attr("data")
        @doc = data[@lang][@cat1][@cat2][@title]

            return false

        @nav.on "click", "li", (evt) =>
            pill = $(evt.target)
            @select_nav(pill)
            return false

        @lvl1.on "click", "li", (evt) =>
            # .closest("li") because of the badge
            t = $(evt.target).closest("li")
            @select_lvl1(t)
            return false

        @lvl2.on "click", "li", (evt) =>
            t = $(evt.target).closest("li")
            @select_lvl2(t)
            return false

        @document.on "click", "li", (evt) =>
            t = $(evt.target)
            @select_doc(t)
            return false
