Flat and Fitted Sheets

     Fitted sheets, sometimes called bottom sheets, are the sheets that cover the mattress on a bed. Fitted sheets often have elastic sewn into each one of the four corners to help it stay in place over the mattress. Fitted sheets, like the other components of bedding, are either sold individually, called open stock, or as part of a complete set. A complete sheet set includes the fitted sheet; the flat, or top sheet; and either one pillow case for twin-sized beds, or two for all other sizes.