Correction - it is a one time activity of correcting or rectifying a mistake/error. E.g. taking a medicine for symptomatic relief from fever
Corrective Action - is the action taken to eliminate the cause of the mistake/error to prevent it from recurring. This involves understanding the root cause and eliminating it. E.g. Identifying the actual reason for fever (viral/bacterial infection) and treating the infection
Preventive Action - is the action taken to prevent a potential mistake/error i.e. before it happens. E.g. maintaining proper hygiene and a healthy lifestyle to build up resistance to infections
An application oriented question on the topic along with responses can be seen below. The best answer was provided by Venugopal R on 5th October 2017.