Observational Comparison of Star Formation in Different Galaxy Types
  Galaxies cover a wide range of masses and star formation histories. In this
review, I summarize some of the evolutionary key features of common galaxy
types. At the high-mass end, very rapid, efficient early star formation is
observed, accompanied by strong enrichment and later quiescence, well-described
by downsizing scenarios. In the intermediate-mass regime, early-type galaxies
may still show activity in low-mass environments or when being rejuvenated by
wet mergers. In late-type galaxies, we find continuous, though variable star
formation over a Hubble time. In the dwarf regime, a wide range of properties
from bursty activity to quiescence is observed. Generally, stochasticity
dominates here, and star formation rates and efficiencies tend to be low.
Morphological types and their star formation properties correlate with
environment.
