Over the course of 50 years Louis Pasteur's discoveries revolutionized chemistry, agriculture, industry, medicine, surgery and hygiene. These discoveries also greatly changed the human condition, and his brilliance and rigorous methods advanced both science and its techniques. In the work of Pasteur, each discovery is a link in an uninterrupted chain, from molecular assymetry to the prevention of rabies via fermentation, silkworm, wine and beer diseases, sterilization and virus/vaccines.
In 1847 he formulated a fundamental law : assymetry differentiates the organic world from the mineral world; in other words, molecular assymetry is the mark of life. His work became the basis of a new science-stereochemistry (or three-dimensional chemistry).
In studying fermentation, he demonstrated that each sort of fermentation is linked to the existence of a specific micro-organism, cultivating it in an appropriate, sterile medium. This is the basis of microbiology.
Pasteur negated the doctrine of spontaneous generation; he also developed a theory on germs. At the same time, his discovery of anaerobic life paved the way for the study of germs of septicemia and gangrene among other infections. Thanks to Pasteur, it became possible to devise techniques to kill microbes and to control contamination. Pasteur demonstrated that wine diseases are caused by microorganisms which could be killed by heating the wine to 55° C. Applied to beer and milk, this process called "Pasteurization" soon came into worldwide use.
Pasteur's study of silkwork diseases led to the discovery of the infectious agents and revealed transmission of these diseases and how to prevent them, an elaboration on his study of fermentation. He was able to confirm that each disease has its microbe and that the microbes are foreign elements. He established the basic rules of sterilization(asepsis) which became critical for surgery and obstetrics.
From 1877 to 1887, Pasteur employed these bases of microbiology in the battle against infectious diseases. He went on to discover successively staphylococcus, streptococcus and pneumococcus.
He discovered the method for the attenuation of virulent micro-organisms and them developed vaccines against chicken pox cholera, anthrax and swine erysipelas. On July 6, 1885, for the first time, he tested his pioneering rabies treatment on man; the young Joseph Meister was saved.
On March 1, 1886 Pasteur presented his result to the Academy of Sciences and called for the creation of a rabies vaccine centre. A huge international public drive for funds financed the construction of the Institute Pasteur. In accordance with Pasteur's wishes, the Institute was founded as a clinic for rabies treatment, a research centre for infectious disease and a teaching institution Louis Pasteur was then 66 years old. He went on to dedicate' the last 7 years of his life to the Institute. His work was pursued and amplified by his disciples, The Pasteuriens.
Pasteur's work is not simply the sum of his discoveries. It is also the revolution of scientific methodology. Pasteur had superimposed two indisputable rules of modem research : the freedom of creative imagination obligatorily subjected to rigorous experimentation. Louis Pasteur was also a humanist, his goal always being the amelioration of the human condition. He was a free man who never hesitated to take issue with the prevailing yet false ideas of his time.
The stamp depicts Louis Pasteur at work originally depicted by Edelfelt (a Finnish painter) recreated in a charcoal sketch. The first day cover is a bronze statue of young Jupille, vaccinated against rabies by Pasteur. The statue by  
Truffaut stands in the Institute Pasteur, Paris.
Source : Information Folder issued by Indian Posts & Telegraph Department, Government of India