Keep calm

Over the last few years, you might have seen a poster similar to this one:

Maybe you've come across it in one of its contemporary usages:

Nonetheless, have you ever heard of the story of the original poster? If not, watch this video and see how it was used during the Second World War:

As you can observe, things we do nowadays have its roots in the past. That's one of the reasons why studying History can be useful and interesting!