Abiogenesis

Life had to have some way to originate from non-living materials
1. The abiotic (nonliving) synthesis of small organic molecules, such as amino acids and nitrogenous bases
2. The joining of these small molecules into macromolecules, such as proteins and nucleic acids
3. The packaging of these molecules into protocells, droplets with membranes that maintained an internal chemistry different from that of their surroundings
4. The origin of self-replicating molecules (autocatalytic-set) that eventually made inheritance possible
rna-world: It's proposed that RNA was the first self-replicating molecule