"Deconstruction" in physics was introduced by Nima Arkani-Hamed, Andy Cohen and Howard Georgi, and independently by Christopher T. Hill, Stefan Pokorski and Jing Wang. Deconstruction is a lattice approximation to the real space of extra dimensions, while maintaining the full gauge symmetries and yields the low energy effective description of the physics. This leads to a rationale for extensions of the Standard Model based upon product gauge groups, G × × G × × G . . . , such as anticipated in " topcolor " models of electroweak symmetry breaking. The little Higgs theories are also examples of phenomenologically interesting models inspired by deconstruction. Deconstruction is used in a supersymmetric context to address the hierarchy problem and model extra dimensions. "Clock models," which have become popular in recent years in particle physics, are completely equivalent to deconstruction.