When masked gunmen stormed the offices of French satirical magazine Charlie Hebdo, they were heard to shout “Allahu Akbar” or “God is Great” in Arabic. That the attackers were Muslim terrorists is without question. So what had Charlie Hebdo published to upset followers of Islam? Turns out they have a long history of satirical (and vulgar) "comedy" aimed at religion – Islam in particular. Here’s a sample along with explanations of what the cartoons depict.