Abstract
Big data is an evolving term that describes any voluminous amount of structured, semi-structured and unstructured data that has the potential to be mined for information. Big Data it's varied, it's growing, it's moving fast, and it's very much in need of smart management In this paper, we first review a literature survey of big data, second review the related technologies, such as could computinq and Hadoop, We then focus on the five phases of the value chain of big data, i.e., data sources, data collection, data management, data analysis and data visualization. And we finally examine the several representative applications of big data.