A number of nations of the world use precancels, typically in the form of an overprint on definitive series stamps. For instance, in France, the overprint is a semi-circle reading Affranches. Many towns and cities of Belgium and the United States have issued precancels printed with the community's name; in the case of the US, some 9,500 distinct examples of "bureau precancels" are known. Some types of precancels include a date as well.

   In the US, overprints have been gradually displaced by special-purpose stamps typically inscribed "bulk rate", "presorted first-class", or "presorted STD".

   The Precancel Stamp Society, formed in 1922 from two previously-existing clubs, specializes in the study of precancels. A number of catalogs list all the types of precancels issued in the countries that use them.

   Source : Wikipédia.

I - Before the Independence of 1924 to 1958

II - After Independence