The UK is the only country that is not required to have its name on the postage stamps.
There are required elements for stamps intended to be used on international mail. An important one of them is the name of the country. The first postage stamps, those of the United Kingdom, had no name. In 1874 the Universal Postal Union exempted the United Kingdom from its rule and stated that a country's name had to appear on its postage stamps, so a profile of the reigning monarch was all that was required for the identification of the UK's stamps. To this day the UK remains the only country not required to name itself on its stamps. For all other UPU members, the name must appear in Latin letters.
Many countries using non-Latin alphabets used only those on their early stamps, and they remain difficult for most collectors to identify today.
The name chosen is typically the country's name for itself, with a modern trend towards using simpler and shorter forms, or abbreviations. For instance, the Republic of South Africa inscribes with "RSA," while Jordan originally used "The Hashemite Kingdom of Jordan," and now just "Jordan". Some countries have multiple allowed forms from which the designer may choose the most suitable. The name may appear in an adjectival form, as in Posta Romana ("Romanian Post") for Romania. Dependent territories may or may not include the name of the parent country.