Principles are mostly high level guidelines and ideals. For example, a principle that a company might have is that all employees should be treated with respect and dignity, or that all employees should be allowed to have a work/life balance. Policies are much more detailed and are usually rules and regulations that are written down somewhere. For example, a company might have a set of policies about how to record your vacation time, and another set of policies about how to request a new computer, and another set of policies on how to deal with problems in the workplace. The word "policy" in this case has almost the exact same meaning as the word "rule". Hop ethos helps!!

The difference between "principle" and "policy". I'm not sure but a principle is being a good leader doing something right, following all the rules. Having good leadership. Policy is a must, following all the rules and if you don't follow it you will have consequences (depending on what you did).