At a glance, Lubricants can be divided into two major categories of automobile lubricants and industrial lubricants. Industrial lubricants are also divided into three major categories of industrial oils, greases and other special lubricants such as metal lubricants and so on.
Lubricants is a solid, semi-solid, liquid and gas substances to reduce friction between two surfaces.
Lubrication or tribology is defined as the science of facilitating the relative movement of surfaces in contact with each other. Lubrication means reducing friction between two surfaces using a lubricant.