Carbohydrates are classified into three main types: 1. Simple Carbohydrates: Found in fruits, milk, and sugar. They are quickly absorbed and can cause rapid spikes in blood sugar. 2. Complex Carbohydrates: Found in whole grains, legumes, and starchy vegetables. They are absorbed more slowly and provide a more gradual increase in blood sugar. 3. Fiber: A type of carbohydrate that is not digested by the body. It helps in maintaining digestive health and can moderate blood sugar levels.