The term "big data" will always be remembered as the big buzzword of 2013. According to the Wikipedia, big data "is a collection of data sets so large and complex that it becomes difficult to process using on-hand database management tools". In other perceptions, the "3 Vs" that characterize it (i.e., volume, velocity, and variety) or the "4 Vs" (adding veracity to the previous three) are responsible for the fact that it exceeds an organization's own data as well as its storage or compute capacity for accurate and timely decision-making. In essence, big data refers to the situation that more and more aspects and artifacts of everyday life, be it personal or professional, are available in digital form, e.g., personal or company profiles, social network and blog postings, buying histories, health records, to name just a few, that increasingly more data gets dynamically produced especially on the Internet and on the Web, and that nowadays the tools and techniques are available for evaluating and analyzing all that data in various combinations. Numerous companies already foresee the enormous business effects that analytical scenarios based on big data can have, and the impacts that it will hence have on advertising, commerce, and business intelligence (BI). This paper reviews the issues, techniques, and applications of big data, with an emphasis on future BI architectures.