Brownian motors, or ratchets, are systems that enable directed transport far from thermal equilibrium, utilizing thermal noise and asymmetric potentials. This review explores the fundamental principles, models, and applications of Brownian motors, emphasizing their ability to generate directed motion without an inherent bias. Key concepts include the Smoluchowski-Feynman ratchet, which demonstrates how thermal fluctuations can be harnessed for transport, and the role of symmetry breaking in achieving directed motion. The review covers various ratchet types, such as pulsating and tilting ratchets, and discusses their physical basis, including thermal environments and nonequilibrium perturbations. It also addresses quantum mechanical effects, collective behavior, and biological applications, such as molecular motors. The review highlights the importance of symmetry, current inversions, and the interplay between thermal noise and external forces. It provides a comprehensive overview of the theoretical and experimental developments in the field, emphasizing the significance of Brownian motors in both physics and biology. The review concludes with a discussion of future directions and the broader implications of these systems in understanding non-equilibrium processes.Brownian motors, or ratchets, are systems that enable directed transport far from thermal equilibrium, utilizing thermal noise and asymmetric potentials. This review explores the fundamental principles, models, and applications of Brownian motors, emphasizing their ability to generate directed motion without an inherent bias. Key concepts include the Smoluchowski-Feynman ratchet, which demonstrates how thermal fluctuations can be harnessed for transport, and the role of symmetry breaking in achieving directed motion. The review covers various ratchet types, such as pulsating and tilting ratchets, and discusses their physical basis, including thermal environments and nonequilibrium perturbations. It also addresses quantum mechanical effects, collective behavior, and biological applications, such as molecular motors. The review highlights the importance of symmetry, current inversions, and the interplay between thermal noise and external forces. It provides a comprehensive overview of the theoretical and experimental developments in the field, emphasizing the significance of Brownian motors in both physics and biology. The review concludes with a discussion of future directions and the broader implications of these systems in understanding non-equilibrium processes.