Autophagy is a self-degradative process crucial for maintaining cellular homeostasis and energy balance during development and nutrient stress. It plays a housekeeping role by removing misfolded proteins, damaged organelles, and intracellular pathogens. Autophagy can be non-selective or selective, targeting specific organelles, ribosomes, and protein aggregates. The process involves the formation of an isolation membrane (phagophore) that engulfs cargo, which then matures into an autophagosome that fuses with the lysosome for degradation. Key regulatory steps include phagophore formation, Atg5-Atg12 conjugation, LC3 processing, cargo selection, and fusion with the lysosome. Autophagy is controlled by signaling pathways such as the target of rapamycin (TOR) kinase, which integrates nutrient sensing and growth factor signaling. Disruption of autophagy has been linked to various diseases, including cancer, neurodegeneration, cardiomyopathy, diabetes, liver disease, and autoimmune diseases. The review highlights the latest findings on the molecular mechanisms and regulation of autophagy, emphasizing its role in preventing diseases and its potential as a therapeutic target.Autophagy is a self-degradative process crucial for maintaining cellular homeostasis and energy balance during development and nutrient stress. It plays a housekeeping role by removing misfolded proteins, damaged organelles, and intracellular pathogens. Autophagy can be non-selective or selective, targeting specific organelles, ribosomes, and protein aggregates. The process involves the formation of an isolation membrane (phagophore) that engulfs cargo, which then matures into an autophagosome that fuses with the lysosome for degradation. Key regulatory steps include phagophore formation, Atg5-Atg12 conjugation, LC3 processing, cargo selection, and fusion with the lysosome. Autophagy is controlled by signaling pathways such as the target of rapamycin (TOR) kinase, which integrates nutrient sensing and growth factor signaling. Disruption of autophagy has been linked to various diseases, including cancer, neurodegeneration, cardiomyopathy, diabetes, liver disease, and autoimmune diseases. The review highlights the latest findings on the molecular mechanisms and regulation of autophagy, emphasizing its role in preventing diseases and its potential as a therapeutic target.