Cells maintain their homeostasis through continuous synthesis and degradation of their components. Impairment in the balance within such cycles can be responsible for the pathogenesis of various human diseases. One major site for intracellular degradation is the lysosome. Lysosomes are spherical, membrane bound organelles that are generated by the golgi apparatus. They contain hydrolytic enzymes, and so function as part of the recycling system of the cell. This review focuses on our present knowledge on, formation, functions, and list of hydrolases of lysosomes.