Wilson loops at large N, strings, and M2-branes

<!--HTML--><p>I will discuss several aspects of the holographic description of Wilson loops in large N gauge theories in terms of strings and membranes in AdS. I will first give an overview of progress made in the past few years on the study of the defect CFT defined by Wilson lines in supersymmetric gauge theory, which leads to an example of AdS2/dCFT1 where the AdS2 corresponds to the fundamental string worldsheet. I will then discuss some new results on reproducing the localization predictions for the strong coupling expansion of the circular Wilson loop expectation value. In particular, I will present a recent calculation of one-loop quantum corrections for an M2 brane with AdS2xS1 world-volume which is holographically dual to the Wilson loop in the ABJM gauge theory in the large N limit with fixed level k. If time permits, I will also briefly discuss similar quantum M2 brane calculations that precisely reproduce the non-perturbative corrections to the free energy of the large N ABJM theory on S3 predicted by localization.</p>