Letter of refusal indicates about appeal. Appeal must arrive to the concerned department within stipulate period of time mentioned on the refusal letter else need to re-apply for visa application.
Visa refusal letter indicates where to appeal whether it is to the High commission/ embassy or to the administrative tribunal or court. It varies from country to country such as in UK the appeal may be file to the first tribunal, Schengen (Europe) country the appeal/ review may be file to the embassy or to the court/ tribunal