Challis is a soft, lightweight fabric made from wool or cotton. It is often used for making dresses and blouses. Orlon is a synthetic acrylic fiber that is lightweight and soft. It is often used to make sweaters and other garments. VOILE is a lightweight, sheer fabric made from cotton or silk. It is often used to make curtains and other window treatments. BALSA is a lightweight wood that is often used in model airplanes and other crafts. It is also used to make lightweight fabrics for clothing.