https://thenextweb.com/google/2018/11/08/google-announces-android-will-support-upcoming-foldable-phones/

Last night, Samsung gave us a glimpse of its eagerly awaited foldable phone, at its annual developer conference. At the same time, Google announced that Android will officially support the foldable form factor.

In a blog post, the company classified foldable phones in two categories: one-screen devices and two-screen devices. The first ‘foldable’ has only one screen which can bend. While the latter has one phone-sized screen and another bendable screen on the inside, as shown on the left in the below graphic. Samsung’s phone falls into the second category.