The continuous growth of social networks and the active use of social media services result in massive amounts of user-generated data. Worldwide, more and more people report and distribute up-to-date information about almost any topic. At the same time, there is an increasing interest in information that can be gathered from this data. The popularity of new services and technologies that produce and consume data streams imposes new challenges on the analysis, namely, in terms of handling high volumes of noisy data in real-time.