Oats are a cereal grain that humans have cultivated for thousands of years, primarily as food for ourselves and our animals. The grain grows in clusters at the top of tall stalks, and when harvested and processed, it becomes the oatmeal you might eat for breakfast or the oats horses munch by the bucketful.

Oats are remarkably nutritious and versatile. When rolled flat and cooked with water or milk, they make a warm, filling breakfast. When baked into cookies or granola, they add a chewy texture and nutty flavor. Farmers also grow oats as feed for livestock, especially horses, which is why someone might say a frisky horse is feeling his oats, meaning he's full of energy.

Unlike wheat or rice, oats have a distinctive, slightly earthy taste. They're also hardy plants that can grow in cooler climates where other grains struggle. For centuries, oats were a staple crop in Scotland and Ireland, where they were ground into flour for bread and porridge.

The word also appears in the phrase sow your wild oats, which can mean to behave in a wild or irresponsible way when you're young.