Big Data is one of the latest emerging topics in the field of business information systems, and is marketed as being the key for companies' future success. Many analytic solutions are offered by IT companies to help other businesses with the flood of data that is generated within and outside of a company. Despite the extensive use of the notion Big Data for marketing purposes, there is no common understanding of how to characterize the elements of the Big Data concept. The authors contribute to the clarification of this concept with a methodologically enriched literature review by deriving characteristic dimensions from existing definitions of Big Data. These dimensions are validated and enriched with a two-step approach by applying topic models on 248 publications relevant to Big Data. The authors propose that the concept of Big Data can be described by the dimensions of data, IT infrastructure, applied methods, and an applications perspective. The assignment of the results to a generic data analysis process reveals that recent publications focus on data analysis and processing, and less attention is given to the initial data selection or the visualization and utilization of the analysis results.