Definition of Oriented Graph:
Basically directed graphs can have an arrow going from $A$ to $B$ and an arrow going from $B$ to $A$. Oriented graphs can have at most one arrow between any two vertices $A$ and $B$.
Definition of Directed Acylic Graph (DAG)
In mathematics, particularly graph theory, and computer science, a directed acyclic graph (DAG) is a finite directed graph with no directed cycles.
An edge from $A$ to $B$ and another from $B$ to $A$ is a cycle right ?
Then if Oriented graphs already do not have such a cycle then how are they different from DAGs ? Unless of course DAGs need some other constraint satisfied ? In that case what are they ?