Postage stamp stamps did not need to show the issuing country, so no country name was included on them. The UK remains the only country to omit its name on postage stamps, using the reigning monarch’s head as country identification. Following the introduction of the postage stamp in the UK, prepaid postage considerably increased the number of letters mailed. Before 1839, the number of letters sent in the UK was typically 76 million. By 1850 this increased five-fold to 350 million, continuing to grow rapidly until the end of the 20th century when newer methods of indicating the payment of postage reduced
Postage stamps and postal history of South Sudan (see illustration). South Sudan is also using postage stamps for other than postage usage. For instance, the application fees for a post office box, 5 SSP, is paid in the form of five 1 SSP stamps, pasted on the application form itself. The central Government of South Sudan, however, has not issued any national revenue stamps. Only Central Equatoria State is known to have issued its own state revenue stamps, which are used on certain documents issued by the state, like Age Assessment Certificates. Central Equatoria State has been using also after independence of South Sudan the old three revenue