This review focuses on the key aspects of lipases. Lipases (EC 3.1.1.3) are triacylglycerol acylhydrolases that act on carboxylic ester bonds. They breakdown triacylglycerides into glycerides (diglycerides or monoglycerides), fatty acids and glycerol. Their mass ranges from 19 kDa for B. stratosphericus to 92 kDa for P. gessardii. Their optimum temperature and pH ranges from 15 °C to 80 °C for Acinetobacter sp. and Janibacter sp. and 5 to 11 for P. gessardii and E. faecium respectively. Lipases chemo-, regio-, and enantio- specific features make them first choice of enzymes in research. Their kinetics for substrate hydrolysis depends on different esters. Mostly lipases are extracellular. Type 1 secretory system (T1SS) and Type 2 secretory system (T2SS) are involved in secreting lipases to external medium. They are found in eukaryotes and prokaryotes including animals, plants and microorganisms. Moreover, bacterial and fungal enzymes have diverse industrial applications in food, health, pharmaceutical, medical, textile, detergent, cosmetic and paper industries. Genetic engineering is employed to improve the properties of lipases. Their increasing demand in market has made them a hot topic in scientific research. Scientists are trying to discover novel lipase producing microorganisms due to their expanding commercial value. Keywords: Lipases, esterification, transesterification, biochemical and physicochemical properties, recombinant DNA technology