Autophagy, the process by which cells recycle cytoplasm and dispose of excess or damaged organelles, has gained significant attention due to the discovery of key protein components. This process is conserved in eukaryotes and can be studied using molecular genetics and biology in various model systems. Autophagy plays a crucial role in maintaining cellular homeostasis and is involved in development, differentiation, and tissue remodeling. It can be induced by environmental changes such as nutrient depletion and is implicated in both protective and detrimental processes in diseases. In programmed cell death (PCD), autophagy can occur independently or as a secondary effect of apoptosis. The relationship between apoptosis and autophagy is complex, with both processes potentially contributing to cell death. Autophagy is also involved in cancer, where it can both promote and prevent tumor growth. In muscular disorders, elevated levels of autophagic vesicles can lead to myopathy, and in neurodegenerative diseases, autophagy may protect against toxic effects of protein aggregates but can also induce cell death. Autophagy plays a role in defending against pathogens by removing them through phagocytosis or autophagy. Some pathogens subvert autophagy to replicate within autophagosomes, while others use autophagy to degrade host cell components for their benefit. In aging, autophagy is associated with longevity, and caloric restriction, which may induce autophagy, has positive effects on lifespan. Despite its importance, our understanding of autophagy's role in health and disease is still in its early stages. Further research is needed to clarify the precise mechanisms and regulatory pathways involved, as well as to develop tools for modulating autophagy to combat or promote specific conditions.Autophagy, the process by which cells recycle cytoplasm and dispose of excess or damaged organelles, has gained significant attention due to the discovery of key protein components. This process is conserved in eukaryotes and can be studied using molecular genetics and biology in various model systems. Autophagy plays a crucial role in maintaining cellular homeostasis and is involved in development, differentiation, and tissue remodeling. It can be induced by environmental changes such as nutrient depletion and is implicated in both protective and detrimental processes in diseases. In programmed cell death (PCD), autophagy can occur independently or as a secondary effect of apoptosis. The relationship between apoptosis and autophagy is complex, with both processes potentially contributing to cell death. Autophagy is also involved in cancer, where it can both promote and prevent tumor growth. In muscular disorders, elevated levels of autophagic vesicles can lead to myopathy, and in neurodegenerative diseases, autophagy may protect against toxic effects of protein aggregates but can also induce cell death. Autophagy plays a role in defending against pathogens by removing them through phagocytosis or autophagy. Some pathogens subvert autophagy to replicate within autophagosomes, while others use autophagy to degrade host cell components for their benefit. In aging, autophagy is associated with longevity, and caloric restriction, which may induce autophagy, has positive effects on lifespan. Despite its importance, our understanding of autophagy's role in health and disease is still in its early stages. Further research is needed to clarify the precise mechanisms and regulatory pathways involved, as well as to develop tools for modulating autophagy to combat or promote specific conditions.