Soft Physics of p+Pb and Pb+Pb Collisions from the ATLAS Experiment at the LHC

The physics of the pPb and PbPb collisions at the LHC covered with the ATLAS detector ranges from the studies of relatively soft sector to the studies of the products of the hard scatterings. In the sector of low transverse momenta, $p_T$, the main areas of interest are the total cross-section or charged particle multiplicities scaling with the number of participating nucleons. Studied in details are also the collective phenomena arising due to the hydrodynamical stage of the system evolution from the initial hard scattered quarks and gluons to the hadronized particles. Recent ATLAS results on the total charged particle multiplicities and differential yields in pPb will be reviewed. The observation of the elliptic flow in the pPb will be also presented. Additionally the novel results on the flow coefficients and their relation to the fluctuations in the initial state of PbPb collisions will also be presented.