Non-stationary Magnetic Reconnection: plasmoids, turbulence, and what it all means

In this contribution the recent progress on understanding the role of secondary tearing instabilities and small-scale turbulence in resistive-MHD reconnection with very large Lundquist numbers $S\geq 10^4$ is reviewed. It is argued that the resulting formation of multiple plasmoids and their rapid nonlinear evolution greatly affect the basic structure of the reconnection layer and force upon us a total revision of the conventional picture of the reconnection processes. In particular, the very definition of the reconnection rate and its scaling with~$S$ are discussed and compared with the results of recent numerical simulations.