Geographic names constitute a very important element of each map, since this is one of the main features characterizing geographical objects. Particular objects have different names in each language, which is the reason why it was decided to standardize geographic names internationally and to recommend the use of geographic names in the official language of each area. However, this process may impoverish local languages in which particular geographic names have often been created over many centuries. Such names are an important element of the Polish cultural heritage,which is one of the reasons for which they should be preserved. Geographic names can be classed into two categories: official and unofficial. The former are the names approved by an agency responsible for geographic names and used within its area of responsibility. The latter group includes all names used in an official language, but differing from the officially appreved forms (Kudowa instead of Kudowa-Zdrój), names in the languages and dialects which are used on a certain area but do not have the states of an official language (e.g. Gduńsk in Cassubian) and also exonyms (names in a language which is not used on certain area - such as Moscau in German or Damascus in English). The ter"exonym" was first used by Marcel Arousseau in 1957 and was then redefined by numerous authors. The United Nations Group of Experts on Geographic Names (UNGEGN), established in 1967 has a very important influence on this term. According to their latest definition an exonym is a name used in a certain language for a place located outside the area, in which that language has the official status, and also differing from an officially approved name. However, particular definition of an exonym often have significant diofferences, and what is even more important, they are not fully precise. The examples of such names probkems may include the areas where there is no official language (Antarctic or the oceans) or when a particular object has no name in an official language (Polish name of CieSniny Duńskie). Other examples may include the names in languages of ethnic minorities. The question aries whether those names should be treated as exonyms, and if so, how different from an official form a geographic name has to be in order to be classed as an exonym. We propose to treat as exonums all names in which a diacritical mark (Peru) and Peru') an article (Gambia and The Gambia) or a declension form (Andy and Andes) was added, omitted or altered. However, the names formed by phonetic transcription or transliteration of an official name and also those formed by translating or omitting a term indicating a particular geographic feature should not be treated as exonyms. Genetically, exonyms can be classed into the following three main groups: 1) proper exonyms - the names characteristic for a particular language; 2) borrowed exonyms borrowing from other languages, and 1) linguistic exonyms (formed by approximation of the official form to the pronunciation and grammatical rules of another language). This last category can be further subdivided into: a) transcription exonyms (transcribed from another language), b) inflection exonyms (formed by adding a prefix, suffix or an article, c) translation exonyms (translated from another language and finally d) errineous exonyms (resulting from an erroneous translation). The transcription of geographic names is a different and equally important problem. The pricess of transcribing is used to perform a phonetic conversion between two languages, and the sounds of the original language are spelled according to the rules of the receiving language. However an important factor against usind the transcription is that more amd more countries using non-Latin alphabets publish topographic maps on which transliteration was applied instead of the ifficial forms.