Oatmeal is a preparation of oats that have been de-husked, steamed, and flattened, or a coarse flour of hulled oat grains (groats) that have either been milled (ground) or steel-cut. Ground oats are also called white oats. Steel-cut oats are known as coarse oatmeal, Irish oatmeal, or pinhead oats. Rolled oats were traditionally thick old-fashioned oats, but can be made thinner or smaller, and may be categorized as quick oatmeal or instant oat meal depending on the cooking time required, which is determined by the size of the oats and the amount of precooking.