如何在2个不同的iframe HTML之间进行通信？

I'm using ruby on rails to develop web app and I have 2 HTML iframe from different file and folder, however, both of them are display at the same link. How can I make them communicate to each other, for example, when I click in the element form iframe 1 and I want the referenced information will be shown at iframe 2?I'm using ruby on rails to develop web app and