# what is the difference between Composite Stellar Population and Galaxy Spectral Energy Distribution?

I am reading Conroy et al. (2013), an extensive review on Stellar Population Synthesis technique, and I really can't get the difference between Composite Stellar Population and Spectral Energy Distribution of a galaxy. The first seems to be luminosity per unit wavelength resulting from the sum of all simple stellar population, considering the effect of dust and a star formation history, the second is the luminosity or the flux per unit wavelength coming from a galaxy.

• The spectrum, and hence the SED, of a galaxy includes light not only from its stellar population, but also other processes such as synchrotron radiation and dust emission.
– pela
Jan 17 at 23:27