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Star formation at high redshift occurs in galaxies with high gas fractions and high turbulent speeds. The morphology is a clumpy disk without an exponential disk, bulge, or bar. There appear to be no exact local analogues, but what comes close are the dwarf Irregular galaxies, which are much lower in mass, along with very rare types called clumpy irregular galaxies, luminous compact blue galaxies, Lyman Break Analogs, etc.. All have a small number of giant star-forming regions, presumably because they are all gas-rich and highly turbulent. The main process of star formation everywhere seems to be gravitational instabilities. The clump masses are large and the rates are large because of the high turbulence and high gas mass fractions. There is a relation between the star formation rate and the galaxy mass versus redshift, called the "main sequence" line. Cosmological models have been made that fit this line fairly well. Generally, the SigmaSFR versus Sigmamol relation is similar to that in local galaxies, with a slight preference for a rate given by the galaxy dynamical time rather than the pure gas dynamical time. In galaxy accretion models, the star formation rate quickly becomes equal to the gas accretion rate. Presumably Sigmamol adjusts to accommodate or enforce this equilibrium.