What do we mean when we talk about confederalism?

The hobby horse of N-VA, the doom scenario of PS: a confederal state. But what exactly is that, a confederal state? Does confederalism mean the division of the country? And do we really become two separate countries? Or can we just continue to work together, but much less? And what is the difference with a federal state? Patricia Popelier is a professor of constitutional law and specializes in federalism. With her "Fifty Shades of Federalism" theory, she is making an international furore. Because the separation between federalism and confederalism may not be as strict as it appears.