A carb is a mixture of carbon, oxygen, and hydrogen atoms, and it looks like lots of dots combine and are tightly packed when you are looking at the structure of the atoms and elements.
Justus Von Liebig discovered the carboydrate compound in mid 1800s
Definition of a carb: Any of a large group of organic compounds occurring in foods and living tissues. Some of these tissues and foods include sugars, starch, and cellulose. Carbs are broken down in an animal body to provide energy for the organism.
Carbohydrates provide energy for your body. The simplest of carbs are sugars, glucose and lactose. One more complex carbohydrate is starch, and it is made by lots of sugar molecules joined together. Carbohydrates are externally acquired or gained from food. The simple sugars such as glucose, fructose, maltose, and sucrose are found in plants. We mostly think of grains as our only source of carbohydrates, but in truth, there are several relevant sources of carbs.
One function of carbohydrates is to provide fuel for the central nervous systeym and energy for muscles. Carbs sometimes prevents protein from being the main source of energy in the body. Carbohydrates also enable fat metabolism. Generally speaking, simple carbs are easily digested and absorbed quicker than other more complex carbohydrates.
Citations: science.jrank.com, livescience.com, google.com