  We present the updated version of the code used to compute stellar
evolutionary tracks in Padova. It is the result of a thorough revision of the
major input physics, together with the inclusion of the pre-main sequence
phase, not present in our previous releases of stellar models. Another
innovative aspect is the possibility of promptly generating accurate opacity
tables fully consistent with any selected initial chemical composition, by
coupling the OPAL opacity data at high temperatures to the molecular opacities
computed with our AESOPUS code (Marigo & Aringer 2009). In this work we present
extended sets of stellar evolutionary models for various initial chemical
compositions, while other sets with different metallicities and/or different
distributions of heavy elements are being computed. For the present release of
models we adopt the solar distribution of heavy elements from the recent
revision by Caffau et al. (2011), corresponding to a Sun's metallicity
Z=0.0152. From all computed sets of stellar tracks, we also derive isochrones
in several photometric systems. The aim is to provide the community with the
basic tools to model star clusters and galaxies by means of population
synthesis techniques.
