Louis Pasteur (December 27, 1822 – September 28, 1895) is a French chemist and microbiologist who was one of the most important founders of medical microbiology.

He is remembered for his remarkable breakthroughs in the causes and preventions of diseases.

His discoveries reduce mortality from puerperal fever, and he creates the first vaccines for rabies and anthrax.

His experiments support the germ theory of disease.

He is best known to the general public for inventing a method to treat milk and wine in order to prevent it from causing sickness, a process that comes to be called pasteurization.

He is regarded as one of the three main founders of microbiology, together with Ferdinand Cohn and Robert Koch.

Pasteur also makes many discoveries in the field of chemistry, most notably the molecular basis for the asymmetry of certain crystals.

His body lies beneath the Institute Pasteur in Paris in a spectacular vault covered in depictions of his accomplishments in Byzantine mosaics.