Explain xkcd: It's 'cause you're dumb.
This link, note 1, may help whomever is going to be editing the comic explanation, I don't have time this morning. [1] Seebert (talk) 13:40, 22 March 2017 (UTC)
Did a quick google and copy/pasted from the Wikipedia page on Moiré patterns. Xseo (talk) 13:51, 22 March 2017 (UTC)