We review computational approaches to understanding the origin of the Initial
Mass Function (IMF) during the formation of star clusters. We examine the role
of turbulence, gravity and accretion, equations of state, and magnetic fields
in producing the distribution of core masses - the Core Mass Function (CMF).
Observations show that the CMF is similar in form to the IMF. We focus on
feedback processes such as stellar dynamics, radiation, and outflows can reduce
the accreted mass to give rise to the IMF. Numerical work suggests that
filamentary accretion may play a key role in the origin of the IMF.