Soil is the medium of plant growth and supports different types of living organisms, including animals and human beings, by providing them with food for their survival. Human existance and settlement is determined by soil fertility as it determines agricultural productivity of an area. Soil determines the natural vegetation and type of crop production of an area. It also influences the landuse of an area. Areas of fertile soil are agriculturally productive and densely populated. It is one of the most important renewable natural resource. Relief, nature of parent rock or bedrock, climate, vegetation and other forms of life (especially decomposers) and time are important factors in the formation of soil. The three most important factors of soil formation are : (i) Nature of parent rock. It influences the colour and texture of the soil. The mineral content of the soil also depends on the parent rock from which it is formed. (ii) Climate influences the rate and types of weathering and erosion of the rocks.Weathering of the parent rocks due to climatic factors and natural forces lead to disintegration of rocks which leads to the formation of soil. (iii) Time determines maturity of the soil. The soil is a living system. It takes millions of years to form soil upto a few centimetres in depth.