The content of this research is designed in seven chapters. The first chapter is introduction of Tribology. It deals with the role of the bearings in machines and the factors that are important for the process of lubrication; such as types of lubricants, types of bearings, geometry of surfaces, types of loading etc. It follows by a discussion on bearing design characteristics. At the tail of this chapter, the review of the related literature is given. The method of deriving the generalized Reynolds type equation with suitable boundary condition for the pressure distribution in a bearing system, is discussed in Chapter-2. This modified Reynolds equation incorporates the effect of magnetic fluid, geometry of surfaces and surface roughness. The analysis carried out in the rest of the work is based on the discussion conducted in this chapter. In fact, the mathematical modeling of the bearing system is treated here. Chapter-3,4,5,6 and 7 are original research work.