The displacement of synchronous generation by converter-interfaced resources is reshaping power system dynamics and has made resonance stability, a category newly recognized in modern stability framework, an increasingly pressing concern. Compared with converter-driven stability, however, resonance stability has received limited systematic treatment and still lacks a unifying perspective that connects its diverse manifestations. This paper revisits resonance from a unified, mechanism-oriented viewpoint, interpreting it as an oscillatory phenomenon arising from strong coupling among closely spaced mechanical, electrical, electromechanical, or control modes of different subsystems or control loops. On this basis, resonance is classified into four types according to the interacting modal pairs, thereby placing classical subsynchronous resonance, electromechanical modal resonance, and emerging converter-related resonances within a single framework. Representative incidents are first reviewed to show how the dominant patterns have evolved from synchronous-machine interactions toward broadband, converter-dominated ones. The main analysis methods are then surveyed and mapped to the resonance types they best address. Finally, mitigation strategies are organized by resonance type around three basic levers: damping injection, impedance reshaping, and modal detuning. The review aims to provide a coherent basis for interpreting mechanisms, selecting methods, and designing mitigation measures in converter-dominated power systems. ... Read more