Millet is related to sorghum, which is used to make the thick dark sweetener, sorghum syrup. Discrepancies exist concerning exactly. There are many varieties of millet, but the four major types are Pearl, which comprises 40% of the world production, Foxtail, and Finger Millet. Pearl Millet produces the largest seeds and is the variety most commonly used for human consumption. Millet is a tall vertical annual grass with an appearance strikingly like to maize. The plants will vary somewhat in appearance and size, depending on variety, and can grow anywhere from one to 15 feet tall. Generally, the plants have coarse stems, growing in dense clumps and the leaves are grass-like, numerous and slender, measuring about an inch wide and up to more than six feet long.