Does a logical system have semantics?
Semantics of a logic describe how to compute the truth value of an expression, possibly given some interpretation. For example, one rule would say that an expression $\varphi \land \psi$ is true iff both $\varphi$ and $\psi$ are true, and another would say that $\forall x \varphi(x)$ is true if for all $x$ in the domain of discourse $D$ (which forms part of the interpretation).

Sometimes the semantics are not obvious – for example, there are different semantics for modal logic. Sometimes we are interested in non-standard semantics, such as 
the semantics of bounded arithmetic described in Forcing with random variables.