E20 can refer to different things, but in the context of fuel, it is a blend of 20% ethanol and 80% gasoline. Ethanol is a renewable fuel derived from natural sources such as fermentation of sugars and alcohol. E20 fuel is used for internal combustion engines in vehicles such as cars, trucks, and bikes. It has been gaining popularity in recent years as more people are looking for cleaner-burning fuels. E20 fuel can provide improved performance in some vehicles due to its higher octane rating and can help reduce emissions since ethanol burns cleaner than gasoline. However, it may cause engine damage if used improperly or in an unsuitable vehicle.