  In these lectures we review how the symmetries of gravitational theories may
be regarded as originating from those of "Yang-Mills squared". We begin by
motivating the idea that certain aspects of gravitational theories can be
captured by the product, in some sense, of two distinct Yang-Mills theories,
particularly in the context of scattering amplitudes. We then introduce a
concrete dictionary for the covariant fields of (super)gravity in terms of the
product of two (super) Yang-Mills theories. The dictionary implies that the
symmetries of each (super) Yang-Mills factor generate the symmetries of the
corresponding (super)gravity theory: general covariance, $p$-form gauge
invariance, local Lorentz invariance, local supersymmetry, R-symmetry and
U-duality.
