The healthcare industry generates a large amount of data, driven by record keeping, patient care, compliance and regulatory requirements. The digitization of the information is called "Big Data", which is capable of supporting a wide range of medical and healthcare functions. Big data analytics (BDA) in healthcare is evolving into a promising field for providing insight from very large data sets and has the potential to improve the quality of healthcare delivery with a reduced cost. BDA has a significant impact on healthcare delivery and holds favourable support in a wide range of medical and healthcare applications that includes clinical decision support, disease surveillance, and population health management. BDA has brought in transformation in healthcare and enabled researchers and practitioners with tools to utilize data generated by healthcare systems globally. BDA also aids in preventing adverse events via early detection and diagnosis, leading to safer cost-effective procedures. In the interest of comprehending and analysing the complex biomedical data now accessible, BDA has become essential for the modeling, validating, and interpreting medical diagnosis through the broad spectrum of bioinformatics, medical imaging techniques, and precision medicine.