Recent observations first made in string theory led to the realization that introducing various ``deformations" (finite volume, appropriate
double-trace operators...) allows for an analytic study of many nonperturbative aspects of arbitrary four-dimensional gauge theories. Notably, the confinement mechanism, the generation of mass gap, and, in some cases, chiral symmetry breaking can be studied in a theoretically controlled manner. In this talk, I will review: i.) the ideas and tools involved, ii.) the main results obtained so far in this approach (and its limitations), iii.) our understanding of its relation to other approaches to (non-)supersymmetric gauge dynamics,
iv.) ongoing and possible future work.