This post deals with lubricants their properties, types and its uses. A study material is also available which can be downloaded from the below link.
Lubricant is a substance which is used to control (more often to reduce) friction and wear of the surfaces in a contact of the bodies in relative motion. A lubricant can be in liquid (oil, water, etc.), solid (graphite, graphene, molybdenum disulfide),or even semisolid (grease) forms.
Lubricants by Jim Livingston on Scribd