The origin and evolution of the atmospheres of Earth, Venus and Mars are reviewed from the time when their protoplanets were released from the protoplanetary disk a few million years after the Sun came into being. The early disk-embedded phase of the evolution of protoplanetary cores that can accumulate gas from the disk and form thin planetary H 2-envelopes is also discussed. This scenario is compared to cases of late stage planet formation, where terrestrial planets accrete from large planetary embryos after the protoplanetary disk already disappeared. The differences between these two scenarios are discussed by investigating non-radiogenic noble gas isotope anomalies observed in the present atmospheres of the three planets. The role of the efficiency of the young Sun's EUV radiation and solar wind to the escape of early atmospheres is also discussed. The catastrophic outgassing of volatiles and the formation and cooling of steam atmospheres after the solidification of magma oceans is addressed together with the geochemical evidence of additional delivery of volatile-rich chondritic materials during the main stages of planetary formation. Unlike early Venus and Earth, no nebula-based H 2-envelope could be accumulated on early Mars due to its low planetary mass. According to the young Sun's luminosity and EUV flux history, Mars' magma ocean related outgassed steam atmosphere could have been lost during the first hundred Myrs. Depending on the young Sun's EUV flux, the presence of greenhouse gases, impacts, and the amount of greenhouse gases outgassed additional to that from the magma ocean, Mars could have developed episodically standing bodies of liquid water

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