  Slightly more than 30 years ago, Whipple detection of the Crab Nebula was the
start of Very High Energy gamma-ray astronomy. Since then, gamma-ray
observations of this source have continued to provide new surprises and
challenges to theories, with the detection of fast variability, pulsed emission
up to unexpectedly high energy, and the very recent detection of photons with
energy exceeding 1 PeV. In this article we review the impact of gamma-ray
observations on our understanding of this extraordinary accelerator.
