  Stellar magnetic fields are produced by a magnetohydrodynamic dynamo
mechanism working in their interior -- which relies on the interaction between
plasma flows and magnetic fields. The Sun, being a well-observed star, offers
an unique opportunity to test theoretical ideas and models of stellar magnetic
field generation. Solar magnetic fields produce sunspots, whose number
increases and decreases with a 11 year periodicity -- giving rise to what is
known as the solar cycle. Dynamo models of the solar cycle seek to understand
its origin, variation and evolution with time. In this review, I summarize
observations of the solar cycle and describe theoretical ideas and dynamo
modeling efforts to address its origin. I end with a discussion on the future
of solar cycle modeling -- emphasizing the importance of a close synergy
between observational data assimilation, kinematic dynamo models and full
magnetohydrodynamic models of the solar interior.
