Big data in healthcare refers to the large set of structured and unstructured data that can be assessed to disclose the trends and patterns in healthcare system for present and future. It also provides the complete data on healthcare related processes such as pre-hospitalization to post medical cost analysis. Big data in healthcare used to predict the epidemics, supporting clinical decisions, enhance the quality of life, and avoid the preventable deaths. The major applications of big data in healthcare include financial analytics, clinical data analytics, and operational analytics. The difficult process of studying Big Data to identify information, such as hidden patterns, market trends, unknown correlations, and customer preferences, aiding businesses in making educated clinical and business decisions is known as Big Data analytics in healthcare. Market growth is predicted to be driven by an increase in demand for Big Data solutions for population health management and a rise in the requirement for business intelligence to optimise health administration and strategy.