The origin of life continues to represent one of the most complex and unresolved questions in modern science, necessitating the convergence of geochemistry, prebiotic chemistry, molecular biology, and evolutionary theory. This work explores the transformation from non-living chemical systems to the first biological forms, placing particular emphasis on the RNA world hypothesis and its connections to alternative models such as metabolism-first and lipid world scenarios. Available evidence supports the feasibility of RNA as an early biomolecule capable of fulfilling both informational and catalytic roles. Nonetheless, significant obstacles remain, including the prebiotic formation of nucleotides, the development of self-replicating ribozymes, and the achievement of high-fidelity replication under plausible environmental conditions. An increasing body of experimental and theoretical research points toward hybrid or co-evolutionary frameworks in which RNA, peptides, lipids, and protometabolic systems interacted from early stages and collectively facilitated the emergence of protocells. Comparative analyses of these competing models suggest that they are more appropriately interpreted as complementary elements within a multistage process, rather than as strictly competing hypotheses. Ongoing unresolved questions—such as the origin of the genetic code, the shift toward DNA–protein systems, and the coordination of replication with metabolism and compartmentalization—highlight the necessity for integrative, experimentally validated, system-level approaches. This study seeks to elucidate the current state of knowledge, identify major conceptual and experimental constraints, and underscore the critical role of integrative frameworks in advancing our understanding of the emergence of life.
