A comforter is a type of bedding made of two lengths of fabric or covering sewn together and filled with insulative materials for warmth, traditionally down or feathers, wool or cotton batting, silk, or polyester and other down alternative fibers. Like comforter, comforters are generally laid over a top bed sheet (and sometimes also blankets).Comforters are usually used in the winter season when it is very cold.
Due to the thickness of a comforter or the amount of down/feathers or other filling it has, a person is insulated against cold.
Comforter sizes correspond with bed sizes: twin, full, queen, king, and cal-king. Comforter sizes run slightly larger than mattress sizes to allow for draping over the sides of the bed. Thick and (sometimes) quilted, a comforter differs from a quilt in that colours are generally dyed and patterns are not embroidered.