History of Star Formation in the Universe

The cosmic history of star formation is briefly reviewed, starting with the Milky Way and then discussing observations relevant to the closed box and hierarchical build-up models. Observations of local star formation are reviewed for comparison. The halo globular clusters appear to have formed in about the same way as today's clusters, with the same IMF and stellar densities, and with a larger mass reflecting the higher pressures of their environments. The bulge of the Milky Way appears to have evolved according to the dissipational collapse model, but other bulges may differ.