Futons made their way into prominence in the 60s and 70s as an informal bed. They were imported from the orient. The material was then cotton batting or layers of cotton tied together. I had one that was a large size. They were very comfortable and very heavy. These days futons are often made of other materials. The old cotton futons could not be washed and so mine didn't last a long time.
Gaucho is the term for the fold out sofa bed usually found in the front section of the Airstream. I'd never heard of a gaucho before I got my Airstream and have never seen it referred to in any way other than an Airstream, but surely it has.