Excerpt from 2 Seat Sofa Bed - Lycksele Lovas Compact & Stylish. :
2 Seat Sofa Bed. In the United Kingdom, a sofa or set is another term for a comfortable seat also used explicitly as a piece of furniture for that. But when referring to a sofa, this is a term used to lie down or bed. The sofa has been used as a place to lie down or to sleep since the early 1900s and is still very popular today. In fact, soft seats or full-size sofa beds are used in almost all homes in America.