This conceptual poster presents the theoretical foundations of resonance in mechanical systems and structures, demonstrating the definition of resonance as a mechanical property associated with the vibration of an object, governed by modal properties, damping, and coupling. We review common applications and extensions to parametric and nonlinear resonance, where applications span vibration isolation and control to structural dynamics in aerospace systems. Advantages include informing design decisions to ensure the accomplishment of engineering objectives. This is leveraged through measurement sensitivity and efficiency distinct to mechanical resonance modeling. Further benefits can be seen in the advancements related to compact design via mode targeting. Key limitations involve sensitivity to uncertainties, fatigue accumulation during experimentation, and simulation limitations. Future research trends emphasize tunable and adaptive resonators, digital twins for real-time modal tracking, and machine-learning–assisted design under uncertainty. The poster maps theoretical undergirding, to design guidelines, to research opportunities, highlighting best practices related to managing resonance safely and effectively.