Duvets are similar to standard comforters, and they can be made of a variety of fillings, e.g. down, cotton and synthetic fibers. They are more popular in colder regions, as they are heavier and provide more warmth than standart comforters and blankets.
A duvet (word originated from France) means a large bag filled with down, feathers, wool or other stuffing to create a warm bed covering. It is similar to quilts, comforters and bedspreads but has its own differences.