How do galaxies form and evolve? A question asked since astronomers (link) in the beginning of the 20th century were able to prove (link) that at least some “nebulae” (link) are at large distances. Spectroscopy (link) is a fundamental tool to explore this question, as it affords a detailed understanding of physical processes (Figure) within the aperture probed by the spectrograph. Imaging (link) in contrast allows to study galaxies over their spatial extent albeit with less information content per spatial resolution element. Integral field spectrscopy (IFS) or imaging spectroscopy allows the combination of the best of both worlds. The Calar Alto Legacy Integral Field Area survey (CALIFA) is an IFS survey of 600 nearby galaxies that runs at the 3.5m telescope (link) at Calar Alto Observatory (CAHA) and uses the PMAS instrument (AIP), delivering spatially resolved maps of their spectroscopic properties. Shown here are 1) broad band images (link) (center up), 2) stellar mass surface densities (upper right), 3) average stellar ages (lower right), 4) diagnostic emission lines (BPT) (lower center), 5) Halpha emission (lower left) and 6) kinematics (upper left). CALIFA data become public (DR1) and allow astronomers worldwide to shed new light on how galaxies form and evolve.