Introduction

An outline is provided of the two main types of solar flare, taking into account the simple-loop (or compact) flare, the two-ribbon flare, and the flare theories which have been proposed. Attention is given to ground-based observations, space observations from Skylab, the preflare build-up, an analysis of the instabilities, the energy release, bulk motions, aspects of particle acceleration, the produced radiation, the storage of magnetic energy and its release, the flux-loop models, the current-sheet theories, and the magnetohydrodynamic equations. It is pointed out that the solar flare owes its existence to the magnetic field. The behavior of the magnetic field during the flare is considered, taking into account the control of the flare plasma by the magnetic field.