Social media enables the gathering of Internet users around the common interests, views and ideas. The main distinguishing feature of social media is the ability to create user generated content (UGC) and widespread use it across the virtual community. Examples of social media are social networking sites (Facebook.com 'service at the head), but also forums and discussion groups, blogs, video sharing services. Social media is characterized by the transaction potential. In the context of support and the establishment of ties between members of the community, there is also the exchange of information that shape the process of purchasing an Internet user. Depending on the source of the impact (community members or businesses, such as lead e-shop on their funpage on Facebook.com), changing the nature of the purchasing process, either at the stage of looking for information about the product / service, either at the stage of making final purchasing decisions. Social commerce generally speaking means using social media in e-commerce. The primary objective of this article is to analyze and evaluate the role of interaction in virtual communities (reflected in social media) on the process of purchasing. The secondary objective is to discuss the matter of social commerce, as well as an indication of synonymous expressions