"Crepe" is the name given to fabric having a crinkled or pebbled texture, often used for blouses and dresses with graceful drape. The word crape is the English form of the French word crepe.
Viscose Crepe. It is a plant based fabric that is processed to give a great feel because of the weight and drape. You can achieve looks that are hard to get with natural fibers like cotton, as it does not stick to under layers and the weight makes it hang close to the body and not bulk out.
Viscose is usually a very soft fabric and crepe has an obvious weave and usually drapes very nicely.
It does have one drawback though, a lack of dimensional stability when washed.