Mathematics and Physics of N=2 Strings

Open and closed strings with two worldsheet supersymmetries in 2+2 dimensional spacetime are reviewed in the NSR formulation. I briefly discuss their quantization, mutual and self-interactions, classical spacetime dynamics and interpretation in terms of self-dual Yang-Mills and gravity. A stringy origin of the infinite self-dual gravity hierarchy is presented. An outlook to the loop level concludes. Talk presented at SQS-99 during 27–31 July, 1999, at JINR, Dubna, Russia