Denim is traditionally made out of cotton and is a type of twill. Denim fabric is made using dyed warp threads, (vertical thread) usually in the an indigo colour, while the weft threads (horizontal threads) were left undyed. This is why the inside of jeans and other denim products often have a much lighter appearance on the inside, this use of two different colour threads gives denim its distinct fading quality as it wears. The name denim derived from the french town where is was first produces Nimes, 'de nimes'. Denim is extremely hardwearding and perhaps one of the most widely used and fashionable dressmaking fabrics around.