diff --git a/src/editor.coffee b/src/editor.coffee
index 1331974cc..ccd8708ec 100644
--- a/src/editor.coffee
+++ b/src/editor.coffee
@@ -1251,11 +1251,9 @@ class Editor
 
   # Public: Transposes the current text selections.
   #
-  # FIXME: I have no idea what this function does.
-  #
-  # This only works if there is more than one selection. Each selection is transferred
-  # to the position of the selection after it. The last selection is transferred to the
-  # position of the first.
+  # The text in each selection is reversed so `abcd` would become `dcba`. The
+  # characters before and after the cursor are swapped when the selection is
+  # empty so `x|y` would become `y|x` where `|` is the cursor location.
   transpose: ->
     @mutateSelectedText (selection) =>
       if selection.isEmpty()