Modelling the ultraviolet/submillimeter spectral energy distributions of normal galaxies

We give an overview of the factors shaping the ultraviolet (UV)/optical - far-infrared (FIR)/submillimeter (submm) spectral energy distributions (SEDs) of normal (non-starburst) galaxies. Particular emphasis is placed on the influence of the geometry of dust and stars on the propagation of light through the interstellar medium. Although strong constraints can be placed on the amount and large scale distribution of dust in disks from the appearance of the galaxies in the optical/UV range, this dust does not account for the observed amplitude and colour of the FIR/submm radiation. Additional, optically thick components of dust associated with the young stellar population on large and small scales are required to account for the complete UV/optical - FIR/submm SEDs. Self-consistent models for the calculation of SEDs of spiral galaxies are reviewed and their prediction for the dust emission and the attenuation of starlight are compared and contrasted