Mustard seeds are from the mustard plant, which is a cruciferous vegetable related to broccoli, Brussels sprouts and cabbage. While there are approximately forty different varieties of mustard plants, there are three principal types used to make mustard seeds: black mustard (Brassica nigra), white mustard (Brassica alba) and brown mustard (Brassica juncea). Black mustard seeds have the most pungent taste, while white mustard seeds, which are actually yellow in color, are the most mild and are the ones used to make American yellow mustard. Brown mustard, which is actually dark yellow in color, has a pungent acrid taste and is the type used to make Dijon mustard. Mustard seeds can be traced to different areas of Europe and Asia with the white variety originating in the eastern Mediterranean regions, the brown from the foothills of the Himalayan Mountains, and the black from the Middle East. Mustard seeds are mentioned in ancient Sanskrit writings dating back about 5,000 years ago. They are also mentioned in the New Testament in which the kingdom of Heaven is compared to a grain of mustard seed. While mustard seeds were used for their culinary properties in ancient Greece, it seems that it was the ancient Romans who invented a paste from the ground seeds, which was probably the ancestor of our modern day mustard condiment. The physicians of both civilizations, including the father of medicine Hippocrates, used mustard seed medicinally. Mustard seed is one of the most popular spices traded in the world today. As it grows well in temperate climates, the areas that produce the greatest amount of mustard seeds currently include Hungary, Great Britain, India, Canada and the United States.