What Are External Environment In Management And How Can We Get The Best Performance Out Of Them?

As per my point of view external environment is the things related to business which not the control of any business men includes govt, customer, supplier ect. Internal environment we handle some how with help of making force on it but external environment is not in over hand.
For example govt. Make any new policy or pass any new tax policy that is not suit to over business or make adverse effect on over company policy. Some time through external environment over business is being vanish. So when ever any top management make any strategy to running business in this competitive world they always think regarding external environment.