Vesuvius enters into the history of volcanology with the 79 AD eruption, which was described very accurately in the letter sent to Tacitus by Plinius the Young, who could observe its whole development from Miseno (20 km far from Vesuvius). More recent, qualitative and quantitative (numerical simulations) studies allow to describe deeply the dynamics of sustained and collapsing plinian eruptions, as well as of the pyroclastic currents associated to this kind of eruptions.