Big data, a new way of managing and interacting with the massive data sets collected and stored by humans. The problem with the massive data collection and distribution systems is to manage this big data as large amount of data that is gathered from various domains of all sizes and types. Most of the captured data clutters lots of storage space because of which it has become a concern of individuals as awareness grows of breadth and depth of personal information being amazed in big data collection. Big data is a concern rather than precise term. In this paper we have discussed big data definitions with various aspects. Then followed by few case studies where in big data is being used. Smart-mall case study is discussed in detail in which customer behavior is analyzed to provide valuable feedback. Apart from that we have discussed issues such as fraud detections, loss of customers, customer behavior prediction etc.

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Big Data Data Streams.