A lubricant is a substance used for decreasing friction between two rough surfaces. It is mostly in a jely-like form. E.g. lubricating oil for machines.
Lubricant is basically an oil. There are bearings in a car or even a skateboard which requires lubircant so the metal will be able to control its temperature and avoid damage from friction and dirt.
If you are talking about Lubricating Oil. The majority of it will be will be a base oil which will be either a mineral or synthetic. There will then be additives which are chemicals which improve the...