The difference between republic act and presidential decree?

1)An "act" implies a law or regulation passed by a legislative body. A 'decree' implies an order or regulation unilaterally issued or declared by someone in authority, without benefit of legislative review or action.

2)The difference would be that a Republic act is an established law formerly legislated by the legislative body and the Presidential would assign a specific act to a societal problem, the act is established and the decree assigns the act.~