Definition: A wittgenstein Prison is a deliberately designed interface (whatever that may mean) that limits your interactions (vocabulary, actions) to a set of allowed things and makes other things practically impossible.
The initial and ultimate Wittgenstein Prison is our language, as observed by Wittgenstein. ("the limits of my language are the limits of my world") In this sense, we are all trapped naturally in our conceptual spaces shaped by our language(s). However, there are also artificial wittgenstein prisons, once we have build. One striking example is the Windows operating system. Others include