A quilt is a multi-layered textile, traditionally composed of three layers of fiber: a woven cloth top, a layer of batting or wadding, and a woven back, combined using the technique of quilting, the process of sewing the three layers together. Occasionally, the three layers of the quilt are tied together using evenly spaced knots rather than sewn. This unique process of binding three layers of fiber together distinguishes quilts from other types of blankets, although in modern British English, an unquilted duvet or comforter may also be called a "quilt." Historically, quilts were frequently used as bedcovers; this use persists today, but in the twenty-first century, quilts are also frequently displayed as non-utilitarian works of art. Where a single piece of fabric is used for the top of a quilt (a wholecloth quilt), the key decorative element is likely to be the pattern of stitching, but where the top is pieced from a patchwork of smaller fabric pieces, the pattern and color of the pieces will be important to the design. Historically, quilts were frequently used as bedcovers or served other functional purposes. However, the work involved in creating them and their decorative possibilities has led to their cultural importance in many places and times, and they are increasingly also treated as a visual art form.