  The standard model of particle physics is an extremely successful theory of
fundamental interactions, but it has many known limitations. It is therefore
widely believed to be an effective field theory that describes interactions
near the TeV scale. A plethora of strategies exist to extend the standard
model, many of which contain predictions of new particles or dynamics that
could manifest in proton-proton collisions at the Large Hadron Collider (LHC).
As of now, none have been observed, and much of the available phase space for
natural solutions to outstanding problems is excluded. If new physics exists,
it is therefore either heavy (i.e. slightly above the reach of current
searches) or hidden (i.e. currently indistinguishable from standard model
backgrounds). We summarize the existing searches, and discuss future directions
at the LHC.
