Autophagy, or 'self-eating', is a conserved cellular process that degrades proteins and organelles, playing essential roles in survival, development, and homeostasis. It is integral to human health, involved in physiology, development, lifespan, and diseases like cancer, neurodegeneration, and microbial infection. Research on autophagy began in the late 1950s, but significant molecular advances occurred in the past 15 years. The term 'autophagy' comes from Greek, meaning 'self-eating', and describes the process by which cytoplasmic cargo is delivered to lysosomes for degradation. Initially, autophagy was thought to be a cellular waste disposal mechanism, but it is now understood to be an adaptive response to stress, providing nutrients and energy. Autophagy is linked to human pathophysiology and has implications for various fields, including cancer, neurodegeneration, immune response, development, and aging. The history of autophagy research focuses on key events over the past 15 years, when molecular understanding of the process began. Early studies in the 1950s to 1980s were based on morphological analyses, leading to the identification of key components like the phagophore and amphisome. The molecular era began in the late 1990s, with studies in yeast revealing autophagy-related genes (Atg genes), leading to molecular analysis in higher eukaryotes. Key findings include the identification of Atg genes, the role of autophagy in selective degradation, and the development of assays to monitor autophagy. Autophagy is regulated by signaling pathways, including the target of rapamycin (TOR) kinase, and is involved in various cellular processes, including cell survival, death, and disease. Autophagy plays a critical role in cancer, neurodegeneration, immunity, aging, and development. It is essential for tumor suppression and can also promote tumor survival under certain conditions. Autophagy is involved in the clearance of damaged proteins and organelles, and its dysfunction is linked to various diseases. Understanding the molecular mechanisms of autophagy is crucial for developing therapeutic interventions. The review highlights the importance of autophagy in health and disease, and the need for further research to fully understand its complex roles.Autophagy, or 'self-eating', is a conserved cellular process that degrades proteins and organelles, playing essential roles in survival, development, and homeostasis. It is integral to human health, involved in physiology, development, lifespan, and diseases like cancer, neurodegeneration, and microbial infection. Research on autophagy began in the late 1950s, but significant molecular advances occurred in the past 15 years. The term 'autophagy' comes from Greek, meaning 'self-eating', and describes the process by which cytoplasmic cargo is delivered to lysosomes for degradation. Initially, autophagy was thought to be a cellular waste disposal mechanism, but it is now understood to be an adaptive response to stress, providing nutrients and energy. Autophagy is linked to human pathophysiology and has implications for various fields, including cancer, neurodegeneration, immune response, development, and aging. The history of autophagy research focuses on key events over the past 15 years, when molecular understanding of the process began. Early studies in the 1950s to 1980s were based on morphological analyses, leading to the identification of key components like the phagophore and amphisome. The molecular era began in the late 1990s, with studies in yeast revealing autophagy-related genes (Atg genes), leading to molecular analysis in higher eukaryotes. Key findings include the identification of Atg genes, the role of autophagy in selective degradation, and the development of assays to monitor autophagy. Autophagy is regulated by signaling pathways, including the target of rapamycin (TOR) kinase, and is involved in various cellular processes, including cell survival, death, and disease. Autophagy plays a critical role in cancer, neurodegeneration, immunity, aging, and development. It is essential for tumor suppression and can also promote tumor survival under certain conditions. Autophagy is involved in the clearance of damaged proteins and organelles, and its dysfunction is linked to various diseases. Understanding the molecular mechanisms of autophagy is crucial for developing therapeutic interventions. The review highlights the importance of autophagy in health and disease, and the need for further research to fully understand its complex roles.