  I review several old/new approaches to the string/gauge correspondence for
the cusped/lightcone Wilson loops. The main attention is payed to SYM
perturbation theory calculations at two loops and beyond and to the cusped loop
equation.
  These three introductory lectures were given at the 48 Cracow School of
Theoretical Physics: "Aspects of Duality", June 13-22, 2008, Zakopane, Poland.
