RNA interference (RNAi) stands as a universally preserved molecular process pivotal in orchestrating posttranscriptional gene suppression throughout a broad spectrum of organisms. This chapter commences with the seminal revelation of RNAi mechanism, tracing its inception from petunias to its ubiquitous occurrence across species. We further dive into the different categories of regulatory noncoding small RNAs, such as small interfering RNAs (siRNAs), microRNAs (miRNAs), and Piwi-interacting RNAs (piRNAs), which have broadened the horizon of RNAi-mediated gene control beyond traditional comprehension. We also explore the significance of RNAi in plant functional genomics and its applications in enhancing crop yield. Finally, we discuss the incorporation of RNAi with other biotechnological methods like gene editing, which has the capacity to influence the trajectory of agriculture and foster sustainable food production in future.