The theme of this paper is the role of social networks in the modern business. Web sites and literature pertaining to the theme were used as references. The theme of this paper is developed through seven main chapters ending with a conclusion. Chapters are organized according to importance, starting with an introduction, which generally decsribes the social networks as a current term of today, methods of data collection and analysis that were required to produce the paper, the goal and the hypothesis. Furthermore, I processed the concept of Web 2. 0 and its impact on business, in order to more closely familiarize the readers with the latest technologies that make up the very core of social networks, but also today's informational techology. Because this chapter mentions contemporary business, which is one of the most important points of this thesis, in the next chapter I developed the concept of modern business, its features, social networks as the main drivers of the development of modern business, the relationship of individuals within the company and social networks, as well as private social networks. The chapter that follows logically builds on the chapter before, and it quotes the six most popular social networks (Facebook, Twitter, LinkedIn, Google +, Pinterest and Tumblr), including their foundation, growth and development, and finally, their registration. Rounded with previous chapters, I dealt with the central section of the dissertation, friends on corporate networks – the employee – employer relationship, which covers topics such as social networks in the business enviroment, and also how social networks affect business companies, as well as methods and analysis techniques of social networks. Finally, with all the processed material, I stated my own conclusion and opinion on the treated matter.