Public health: 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: The public health approach involves-

 1. Defining and measuring the problem. 

2. Determining the cause or risk factors of the problem.

3. Determining how to prevent or eliminate the problem.

4. Implementing effective strategies on a larger scale and 

5. Evaluating the impact.