After its more than 80 years long history, the dynamo problem has finally approached to the goal of one’s ambition to unveil its grand mystery of creation and reversal of the geodynamic field in a self-consistent fasion. The success in unveiling this long mystery of the dynamo problem has been brought by elaborate large-scale computer simulations. In this review, a brief history of the dynamo problem, both theoretical and observational, is first described. Then the recent exciting demonstrations of the generation and reversal of the self-excited dipole-like magnetic structure done by the UCLA-LANL group and the NIFS group are described.
