What is the difference between mineral oil and semi-synthetic oil?

[DelJuliet]

Mineral oil and semi-synthetic oil differ in that: mineral oil is refined from petroleum as a base and then mixed with additives; semi-synthetic oil is synthesized through chemical methods and then mixed with additives. Automotive oil is a lubricant for the engine system, possessing certain anti-oxidation, anti-wear, and anti-corrosion properties. The functions of oil are: 1. As a lubricant, it reduces friction and damage between moving parts; 2. As a coolant, it absorbs heat generated in the engine combustion chamber and piston top, cooling the engine and protecting it from overheating. 3. As a sealant, it fills the space between the piston rings and cylinder liner to prevent the leakage of combustion pressure.