The forward converter is a DC/DC converter that uses a transformer to increase or decrease the output voltage (depending on the transformer ratio) and provide galvanic isolation for the load. With multiple output windings, it is possible to provide both higher and lower voltage outputs. It operates in a manner similar to the flyback converter, but is generally more energy efficient.
A flyback converter stores energy as a magnetic field in an inductor airgap during the time the converter switching element (transistor) is conducting. When the switch turns off, the stored magnetic field collapses and the energy is transferred to the output of the flyback converter as electric current. The flyback converter can be viewed as two inductors sharing a common core. In contrast the forward converter (which is based on a transformer) does not store energy during the conduction time of the switching element - transformers cannot store a significant amount of energy unlike inductors. Instead, energy is passed directly to the output of the forward converter by transformer action during the switch conduction phase.