Social networks are used by millions of people and have therefore become a global communication phenomenon. In the beginning, social networks served the purpose of connecting people, simple communication, sharing content, however, today they are used more and more in business. The appearance of social networks has shaken up the entire world, especially in the field of communication. Their appearance is crucially important in development of each company, especially the small ones. Using social networks in the business world is growing unstoppably, and each day there are new ways and possibilities of performance improvement. The opportunities opened by social networks to individuals and the society are opened to the companies too. It is up to the companies wheter they will recognize the possibilities before them whereas depending on the speed of such recognition, their competitive advantage shall be determined. Marketing, CRM, human resources are just some of the areas for which social networks are used. Further on, social networks open a number of possibilities in those and other areas. Small companies, equally as all others, should constantly monitor the situation on the market, use opportunities and avoid threats. Surely, this requires recognition of advantages and avoiding of disadvantages arising from social networks. All in all, this paper aims at emphasizing the role of social networks in the aforementioned business areas and at drawing attention on small companies in order to determined how are they using them and are they successful in using the advantages arising from it.