Invited review abstract

The analysis of data acquired by ground-based telescopes and by space-born missions, such as the YOHKOH, SOHO, TRACE, RHESSI and HINODE satellites, had helped us to study the phenomena observed during solar flares and to elaborate new theoretical models in order to explain the physical mechanisms involved in these events. These models claim that some destabilizing processes, such as the emergence of new magnetic flux or horizontal photospheric motions, can produce an increase in magnetic energy and the loss of equilibrium. As a consequence, the magnetic field releases the surplus of energy by means of magnetic reconnection processes, in such a manner as to rearrange itself in a new, less energetic, equilibrium configuration. In particular, in this review I will present the contribution given by recent observations to our understanding of the physical processes occurring in solar flares, with special emphasis on the magnetic field environment and evolution.