ON HISTORY OF STUDYING UNOFFICIAL NAMES

Scientific interest in informal anthroponyms as an integral component of the anthroponymic system has a long linguistic tradition. 
Whereas surnames and first names are thoroughly analyzed in onomastic research, nicknames (individual, family), family names, pseudonyms have not been studied enough. Unofficial anthroponyms also reflect the characteristic features of the speech of a certain territory. This enables researchers to trace the interaction of official and folk naming systems. Theoretical analysis of works on anthroponymy made it possible to outline a number of linguistic problems and different approaches to their solution. 
The article analyzes the state of research on Slavic unofficial anthroponymy, since the research analysis of unofficial anthroponyms contributes to the development of methods of presenting one's own facts, establishing the main topical aspects of studies on nicknames, family names. 
The works of M. Khudash, P. Chuchka, and R. Ostash are extremely valuable for Ukrainian anthroponymy; they have become the theoretical basis for many studies on anthroponymy. 
The study revealed that representatives of different schools and areas approach classification of nicknames in different ways. Among all analyzed approaches proposed by scientists, P. Chuchka's classification is the most fully developed. Family names also play an important role in the folk naming system.