Brunette Girl Posing At Home On The Couch

The traditional meaning of couch is a particular type of sofa with a half back and one raised end. By this definition it more closely resembles a daybed, chaise longue, or indeed a bed. In the UK, where the generic term for the item of living room furniture is usually "sofa" or "settee", the term "couch" retains this specific meaning, for example in a therapeutic setting (e.g. a psychiatrist's couch). A couch is therefore used while lying down, while a sofa or settee is for sitting upright. The word "couch" derives from Old French couche, meaning "bed", and from coucher, meaning "put to bed, lay down".
Types
The most common types of couches are the "loveseat", or British two-seater, and the settee or sofa, with two or more seats. A sectional sofa, often just referred to as a "sectional", is formed from multiple sections (typically two to four) and usually includes at least two pieces that join at an angle of 90 degrees or slightly greater, used to wrap around walls or other furniture. A sectional sofa is known as a corner sofa or corner suite in the UK.