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 ∣Vtb∣.
We will present the current status of searches and observation and discuss the
results obtained so far and perspectives at hadron machines.Comment: Invited Report, to appear in Proceedings of Hadron Collider Physics
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