The theory suggesting how life on Earth originated from simpler compounds is known as the abiogenesis theory. This hypothesis posits that life began through natural processes from non-living matter, particularly through the synthesis of organic molecules under prebiotic conditions. Key experiments, such as the Miller-Urey experiment, have demonstrated the potential for amino acids to form from inorganic substances. Though the exact pathway remains uncertain, abiogenesis theories form the basis of our understanding of life's origins on Earth.