Much of the less expensive polyester bedding fabric on the market is described as satin, and because “satin” sounds so close to “sateen,” they want to be sure they are getting a cotton fabric. The two terms are intentionally similar because they both refer to the special weave that makes a fabric with a smooth, soft hand.
Satin - is a smooth, shiny fabric usually made from rayon, nylon, or silk.
Sateen - is a smooth (but not shiny) cotton fabric.
Sateen cotton is the most popular, fabric of choice for luxury cotton bed sheets because they are so smooth and cottony soft. Satin fabrics are very popular for bed and throw pillows and a whole sheets set will create a very silky, sensuous experience in bed.