The most common types of couches include the two-seater, sometimes referred to as a loveseat, and the sofa. The loveseat is designed for seating two people, while the sofa has more than two cushion seats. A sectional sofa, often just referred to as a "sectional", is formed from multiple sections (typically two, three, and four) and usually includes at least two pieces which join at an angle of 90 degrees or slightly greater. Sectional sofas are used to wrap around walls or other furniture.
Other variants include the divan, the fainting couch (backless or partial-backed) and the canapé (an ornamental three-seater). To conserve space, some sofas double as beds in the form of sofa beds, daybeds, or futons.
A furniture set consisting of a sofa with two matching chairs is known as a "chesterfield suite" or "living-room suite". In the UK, the word chesterfield was used to refer to any couch in the 1900s. A chesterfield now describes a deep buttoned sofa, usually made from leather, with arms and back of the same height. The first chesterfield, with its distinctive deep buttoned, quilted leather upholstery and lower seat base, was commissioned by Philip Stanhope, 4th Earl of Chesterfield (1694–1773).
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