Hi Susan!

The solar magnetic field is continuously generated by electric currents inside the Sun. These currents are produced by the flow of hot gases in the Sun. Sunspots are regions of particularly strong magnetic fields that rise deeper from the Sun through its surface. Solar flares and coronal mass ejections that are the strongest manifestations of solar activity are magnetic strutures on the Sun that get unstable for some reason and are suddenly expelled away from the Sun. The Sun's magnetic field is very complex and it changes constantly in time. Thus, it is very difficult to predict when these solar eruptions will happen.

Emilia