Biochar is a carbon-rich source which is produced by burning organic matters like agricultural waste, dung, pinewoods, rice, and maize husk. The process of producing biochar is a temperature dependent and an endothermic process. The process takes place in absence of oxygen at a specific temperature governed by slow or fast pyrolysis. The ancient technique of burning agricultural wastes and other materials only led to increase in the greenhouse gases and global warming. With advent of this technology it not only proved to increase the quality of a soil by enhancing the nutrients and retention of minerals but also plays a great role in the waste-water treatment. The surface of a biochar acts as a great adsorbent for several ions, inorganic materials, and other pollutants. Its surface has active sites containing functional groups of carboxylate –COOH and hydroxylate –OH which forms several bonds like hydrogen, covalent, electrostatic, and non-covalent bonds with the anionic contaminants to be removed from the aqueous medium. Biochar act as one of the finest sorbent as compared to an activated charcoal and has highest efficiency. Apart from the function of certain functional groups on the surface of a biochar in adsorption other factors like temperature, dosage of biochar, pH of a solution also equally plays an important role in the work efficiency of a biochar. The nature of biochar has a direct influence on the effectiveness of sorption which needs to be taken care, as biochar produced from swine dung has large mass and shows less efficiency in adsorption as compared to biochar derived from the agricultural products.