a) Base oils

- Minerals: derived through crude petroleum refining (without synthesis)

- Synthetics: produced by synthetic reactions in chemical process industries

	Hydrocarboned (PIB, PAO…)
	Oxygenated (esters, polyglycols…)
	Miscellaneous
	Halogenated (PFPE…) Silicones etc.

Mixtures of different base metals are often made, which may or may not belong to the same category.

The properties that differentiate the base oils are mainly:
- intrinsic lubricity
- solvent properties
- temperature stability
- behavior at low temperature (liquid / solid transition)
- viscosity index (translates the viscosity variation according to the temperature)
- ignition point
- biodegradability

b) Additives

Compounds of mineral or organic origin and various functionalities:

- anti-friction
- anti-wear
- extreme pressure
- anti-freeze (flow point depressants)
- preservative agents (stabilization of the oil)
- anti-corrosion for lubricated metal surfaces (iron, copper, aluminum…)
- thickeners
- viscosifiers
- detergents, dispersants
- anti-foaming agents
- etc.

c) Application examples

Mineral oils:

- Maintenance lubricants:
	4-stroke diesel engine oils
	general engineering oils
	oils for turbines
- Hydraulic fluids
- Quenching fluids
- Machining and stamping neat oils

- Synthetic oils:

- Maintenance lubricants:
	4-stroke gasoline engine oils
	gearbox and transaxle oils
	oils for compressors
- Fire-resistant and biodegradable hydraulic fluids (HFD)
- Mold oils for rubber vulcanization
- Wire drawing oils