Perhaps I was not clear. I thought that the joke ended in &quot;opin&quot;. I read it a few times, thinking that it didn&#x27;t continue beyond &quot;opin&quot;. Then I notice the link and that the joke continue.<p>Anyway, thanks for the explanations, because I didn&#x27;t get all the details. Perhaps they can add an explanation wiki like <a href="http:&#x2F;&#x2F;explainxkcd.com&#x2F;" rel="nofollow">http:&#x2F;&#x2F;explainxkcd.com&#x2F;</a>