|When the equilibrium conditions of the fully ionized and magnetized plasma are perturbed in localized tubes, a variety of magnetohydrodynamic (MHD) modes (e.g., kink, sausage, torsional, and slow) can be generated. Depending upon the physical nature of the drivers and ambient conditions, standing MHD modes and their harmonics can be excited in these magnetic flux tubes. The wave harmonics generated contain vital diagnostic information about the local plasma and magnetic field conditions, as well as, provide clues about wave dissipation processes. We use the theoretical approach of the MHD seismology, or called as solar magneto-seismology (SMS) when applied to the Sun, for fast and slow tubular waves to demonstrate how to gain insight into the sub-resolution properties of flux tubes. We also discuss the physical significance in diagnosing astrophysical plasma. Future implications of refined SMS and its applications will conclude.