Single Top Physics at Hadron Colliders

The production of top quark in electroweak processes was first observed in 2010 at the Tevatron. Since then it has been carefully studied at both LHC and Tevatron. Single top production proceeds through different channels and allows a direct determination of Cabibbo-Kobayashi-Maskawa matrix element $\mathrm{\mid }{V}_{tb}\mathrm{\mid }$. We will present the current status of searches and observation and discuss the results obtained so far and perspectives at hadron machines.