What does 0w20 engine oil mean?

[Sophia]

0w20 engine oil, the 'w' stands for winter. The number before 'w' represents the freezing point temperature, with common 0w indicating -35 degrees Celsius. The number after 'w' represents the kinematic viscosity of the oil at 100 degrees, with '20' being one of the lower grades in the oil classification. The composition of the oil grade includes two parts: classification and viscosity specification. The oil classification is represented by a combination of two letters. Those starting with 's' are for gasoline engines, those starting with 'c' are for diesel engines, and those with both 's' and 'c' are universal oils for both gasoline and diesel engines. The further the letter is in the alphabet, the higher the quality grade. The grade indicates the oil viscosity. The smaller the number, the better the fluidity in low-temperature environments, the lower the usable environmental temperature, and the better the protection for the engine during cold starts.