Enzymology is the study of enzymes. Enzymes are very cool proteins which act as biological catalysts, speeding up the rate of reactions. Non biological catalysts also exist and you may be familiar with one in your car called a catalytic converter, however these generally require high temperatures and pressures. Because enzymes function in less extreme environments, they enable life to exist, because without them, the chemical reactions that take place in life would not happen, or happen so slowly as to make life impossible at normal temperatures and pressures.