Network name as a primary factor in self-presentation shapes the first impression of the user in the virtual world, becoming an integral component of achieving the set goal. The purpose of this article is to analyze the concept of a nickname, define its essence, highlight characteristic features, and understand its main functions. In particular, the specific character of nickname definitions in lexicographical works and scientific research papers have been studied. It has been determined that contemporary linguistic works actively discuss the issue of internet communication in general and the functioning of linguistic naming units in particular. The revised the following characteristics of nicknames highlighted by the vast majority of researchers have been identified: definition of this concept suggested in the paper is crucial for our research. Moreover, a real or fictional name, a pseudonym, an alias utilized by users for internet communication; the place of use – chats, forums, blogs; the place of communication – the global network, communication on the internet in general. Furthermore, it is important to highlight specific features of nicknames, considering that communication in social networks, chats, forums, and self-presentation in them undergo constant changes. Therefore, this article characterizes the common and distinctive features of a network name and similar onyms as the login name (loginonyms) (presented in computer discourse), an alias, pseudonym, and cryptonym (recognized in onomastics). Common features of a nickname and an alias include the ability to create an unlimited number of onyms for one person, therefore hiding the real identity and modeling a fictional one; as well as non-conventionality of the form and fictionality of the name. Similarly to login names (loginonyms), nicknames are specific types of proper names in the field of Internet communication. Moreover, cryptonym, login name (loginonym), and network name are used in written form. Additionally, the article defines the marking features of network names. Since a nickname is a multifunctional phenomenon, the functional-semantic potential of nicknames is outlined in this scientific research. As a result, it has been revealed that the functions of network names should be categorized depending on the place of their use.