What is the difference between policy and plan?

Policy is quitely  defined in term 'course of action'

Whereas A strategy is a solution to move from current position towards the set future goal.  

policy is came from the company while plan is came from by the management.

Policy is the organization strategey and rules made to be followed by specific details of what to do.

Plan is a steps to be taken to accomplish the goal, it is the way to success by how, when, who and what

Policy is from the company.

Plan is from the manager.