Black sesame seeds are sold with their hulls intact, unlike the lighter color of white sesame that has had the hull removed. This typically gives a product that is slightly more bitter, with a more granular texture.
Black sesame is used in a number of dishes where more texture or bitterness is desired, or for the visual drama of its dark color. Japanese kuro neri goma (black sesame paste) is used as a filling for wagashi confectionery, and some Chinese tong sui (sweet soups) use black sesame.