The social networks are becoming very popular among both general users and companies. More and more firms are using them as an efficient tool of advertising and promoting themselves. Today, there exist plenty of social networks. Among them, Facebook and Twitter are the most world-wide popular and well-known. Besides, some countries have their own ones, as in case of Russia where the leading social network is Vkontakte. The aim that this thesis faces is to make an observation how social networks are used in different countries, to compare the results and give recommendations to the studied countries France, Russia and Sweden in the example of Subway Company. Besides, another aim of our thesis is to provide Subway Vietnam with recommendations about how to be as efficient as possible on Facebook, based on the three observed countries: France, Russia and Sweden. The social networks are start to be discussed in the scientific literature, thus there is not enough of suitable literature. Still we chose the content strategy and social media as the leading frame of reference. These theories accompanied with method we chose in our observation and analytical part. Our chosen method is qualitative approach with netnography and interview tools applied for the case study in the example of Subway Company in France, Russia, Sweden and Vietnam. The observations and analysis are made individually to every country and later compared in a summarizing table in order to provide recommendations to every country and particularly to Vietnam which Subway has just entered. This thesis is contributed to Subway Company and its local branches particularly in France, Russia, Sweden and Vietnam. In general, this work can be regarded as guidelines for companies that use social networks in the promoting aims.