|Public health is defined as the science of protecting the safety and improving the health of communities through education, policy making and research for disease and injury prevention. Public health approach to medicine that is concerned with the health of the community as a whole. Public health is community health. Its activities aim to provide conditions in which people can be healthy and focus on entire populations, not on individual patients or diseases. Review articles are the summary of current state of understanding on a particular research topic. They analyze or discuss research previously published by scientist and academicians rather than reporting novel research results. Review article comes in the form of systematic reviews and literature reviews and are a form of secondary literature. Systematic reviews determine an objective list of criteria, and find all previously published original research papers that meet the criteria. They then compare the results presented in these papers. Literature reviews, by contrast, provide a summary of what the authors believe are the best and most relevant prior publications. The concept of "review article" is separate from the concept of peer-reviewed literature. It is possible for a review to be peer-reviewed, and it is possible for a review to be non-peer-reviewed.