Carbohydrates are divided into two types, simple and complex. The classification is based on the chemical structure and reflects how quickly sugar is digested and absorbed.
Simple carbohydrates are also called simple sugars and are chemically made of one or two sugars. A simple sugar can be just what the name implies, the sugar in your sugar bowl. Things like candy, syrups, and soda pop are also straightforward examples of simple carbs. They are absorbed quickly -- just think how fast sugar-based candy melts in your mouth.
Simple carbs also include foods such as fruit and milk. These are better sources of simple carbs because they contain vitamins and fiber, and also important nutrients that your body needs, like calcium.
Complex carbohydrates are also known as starches and are made of three or more linked sugars. Grains such as bread, pasta, oatmeal and rice are complex carbs, as well as some vegetables like broccoli, corn legumes such as kidney beans and chick peas. They take the longest to digest.
"Carbohydrates." Harvard School of Public Health Nutrition Source. 2006. Harvard School of Public Health. 29 Nov 2006