The air-fuel mixture is a combination of air and fuel that is essential for combustion in internal combustion engines, such as those found in cars and motorcycles. The correct ratio of air to fuel ensures efficient engine performance, power generation, and reduced emissions. Typically, this mixture is around 14.7 parts air to 1 part fuel by weight, known as the stoichiometric ratio. In engines, the air-fuel mixture is drawn into the combustion chamber, where it is compressed and ignited. This process produces energy that powers the vehicle. Factors like engine design, operating conditions, and fuel type can affect the ideal air-fuel mixture, making it crucial for optimal engine efficiency and longevity.