The article ‘The Importance of Social Media in Science’, which consists of two parts, discusses the subject of social media. The first part presents the development of social media over years in figures, as well as the opportunities and risks that are inherent elements of human activity. It shows how the sense of anonymity influences care for the quality of statements and linguistic correctness, as well as demonstrates behaviors of users which cause changes in their security. The second part of this article is the result of research conducted among the Internet users. It refers to their understanding of the term ‘social media’, whereas the main goal is to present the ways of using such media.