The usage of online social networking sites has never been stronger for the individuals and for the companies. This paper is underlining the importance of using the online social networking (OSN) sites in the communication strategy of one’s company; it presents the concept and the evolution of this marketing tool. It points out the advantages and disadvantages of using such a platform in a marketing campaign. We are underlining the strengths and weaknesses of this tool, as well as the main tactics and actions that the company must use in order to achieve the desired / maximum result when using such a communication platform in its strategy. At the same time we are presenting several results of a quantitative marketing research about how the OSN sites influence the consumers and the buying behaviour.
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