This article offers rigorous overview of diverse transduction methods that have enabled successful development of Micro/Nanoelectromechanical Systems (MEMS/NEMS) components and devices used for sensing and actuation. The paper focuses on providing educational insights on the transductions used in MEMS/NEMS, and curates the latest applications and design trends. The review begins by classifying various transduction techniques, explaining cross-domain couplings, presents an underlying working principles and governing equations that drive transducer operation. Both actuation and sensing modes of each transduction method are exclusively explained and discussed, accompanied by the latest case study examples and references. The article provides detailed scientific insights into the widely used transduction techniques in MEMS/NEMS, addresses effective comparative performance of one over another (force, displacement, resonance frequency, quality factor, noise, nonlinearity, energy requirements, etc.) The paper also highlights emerging materials and fabrication platforms using which these transducers are developed