  Einstein's Special Theory of Relativity was proposed a little over a hundred
years back. It remained a bedrock of twentieth century physics right up to
Quantum Field Theory. However, the failure over several decades to provide a
unified description of Electromagnetism and Gravitation or alternatively,
Quantum Theory and General Relativity has finally lead researchers to abandon
the differentiable spacetime manifold on which all of the above was based. In
the most recent approaches we consider a spacetime that is discretized or is
noncommutative. This immediately leads to corrections to the Special Theory of
Relativity, more specifically to Lorentz Symmetry. It is quite significant that
there are observational indicators, particularly in ultra high energy cosmic
rays which suggest that such corrections are indeed there. We examine the whole
issue in this paper.
