Microbial fuel cells (MFCs) have gained attention for converting organic waste into electricity through microbial catalysis. This review discusses the history, mechanisms, materials, and applications of MFCs. MFCs differ from conventional fuel cells by using biotic catalysts at the anode, operating at moderate temperatures, and utilizing complex biomass as fuel. The review highlights the development of bioelectrochemical systems (BESs), including microbial electrolysis cells (MECs), microbial desalination cells (MDCs), and microbial electrosynthesis cells (MECs). Key aspects include electroactive biofilms, electron transfer mechanisms, anode and cathode materials, and practical applications. The review also addresses challenges such as low energy output, electrode interactions, and the need for efficient catalysts. Cathode catalysts, particularly those based on carbon, platinum-group metals, and PGM-free materials, are discussed, along with their reaction mechanisms. Anode materials include carbonaceous and metallic options, each with unique properties. The review emphasizes the importance of surface chemistry and morphology in enhancing biofilm interactions. Despite progress, challenges remain in scaling up MFCs for industrial applications. The review concludes with the potential of MFCs in wastewater treatment and sustainable energy generation.Microbial fuel cells (MFCs) have gained attention for converting organic waste into electricity through microbial catalysis. This review discusses the history, mechanisms, materials, and applications of MFCs. MFCs differ from conventional fuel cells by using biotic catalysts at the anode, operating at moderate temperatures, and utilizing complex biomass as fuel. The review highlights the development of bioelectrochemical systems (BESs), including microbial electrolysis cells (MECs), microbial desalination cells (MDCs), and microbial electrosynthesis cells (MECs). Key aspects include electroactive biofilms, electron transfer mechanisms, anode and cathode materials, and practical applications. The review also addresses challenges such as low energy output, electrode interactions, and the need for efficient catalysts. Cathode catalysts, particularly those based on carbon, platinum-group metals, and PGM-free materials, are discussed, along with their reaction mechanisms. Anode materials include carbonaceous and metallic options, each with unique properties. The review emphasizes the importance of surface chemistry and morphology in enhancing biofilm interactions. Despite progress, challenges remain in scaling up MFCs for industrial applications. The review concludes with the potential of MFCs in wastewater treatment and sustainable energy generation.