Knowing the terminology of men's formal wear will help you decide what colour suit to wear to a wedding. If you are informed that you are going to a black-tie affair, that means you should wear black tie, without exception. The wedding planner and bride probably envision this being an elegant soirée. Stick with a traditional black dinner jacket, white shirt and black bow tie. If the wedding is black-tie optional, you can wear a different colour suit besides black. Stick with classic dark colours to avoid standing out.