The history of life describes the chronological development of biological forms on Earth, beginning with the transition from non-living chemical compounds to self-replicating molecular systems. This process, known as abiogenesis, led to the emergence of the earliest forms of life, which were simple, single-celled organisms lacking complex internal structures. Over immense geological timescales, early life diversified through biochemical pathways, progressing from anaerobic metabolisms to utilizing oxygen. Key evolutionary transitions included the development of cellular complexity, marked by the establishment of internal organelles, and eventually the emergence of multicellular organisms. This trajectory culminated in the vast array of life forms, characterizing the ongoing process of biological adaptation and diversification across the planet's biospheres.