Corn ethanol is a type of biofuel made from the fermentation of sugars found in corn. It is commonly used as an additive in gasoline to help reduce greenhouse gas emissions and improve engine performance. The production process involves converting corn starch into sugars, which are then fermented by yeast to produce ethanol. This renewable energy source is often promoted as a way to decrease reliance on fossil fuels. However, its production can also raise concerns about land use, food supply, and environmental impacts, as large amounts of corn are needed to produce significant quantities of ethanol.