:class:`~hooke.engine.CommandEngine` runs in a subprocess, which
allows command execution to occur in parallel with
:class:`~hooke.ui.UserInterface` interaction. The two processes
-communicate via two :class:`~multiprocessing.Queue`\s.
+communicate via two :class:`multiprocessing.Queue`\s.
There are a number of special classes availiable to structure queue
communications. See :mod:`~hooke.interaction` and