Metal abundances of galaxies stellar populations: estimates and implications for galaxy evolution

The metal abundances of galaxy stellar populations are the result of the interplay between star formation, gas recycling and galaxy environment interactions. Tracing metallicities and abundance ratios, together with ages and masses, for galaxies of different types and over cosmic time can shed light on galaxies star formation efficiencies and quenching mechanisms and can help us better connect progenitors and descendants.
I highlight some observational results in this respect and few related open questions. This goes together with a discussion of some observational and methodological requirements. Ongoing and planned spectroscopic surveys and upcoming facilities have the potential to address these issues and further our understanding of galaxy physical properties.