  The Orion Nebula Cluster (ONC) is the closest site of very young ($\sim$ 1
Myrs) massive star formation. The ONC hosts more than 1600 young and X-ray
bright stars with masses ranging from $\sim$ 0.1 to 35 $M_\odot$. The Chandra
HETGS Orion Legacy Project observed the ONC with the Chandra high energy
transmission grating spectrometer (HETGS) for $2.1\,$Ms. We describe the
spectral extraction and cleaning processes necessary to separate overlapping
spectra. We obtained 36 high resolution spectra which includes a high
brilliance X-ray spectrum of $\theta^1$ Ori C with over 100 highly significant
X-ray lines. The lines show Doppler broadening between 300 and
$400\;\mathrm{km}\;\mathrm{s}^{-1}$. Higher spectral diffraction orders allow
us to resolve line components of high Z He-like triplets in $\theta^1$ Ori C
with unprecedented spectral resolution. Long term light curves spanning
$\sim$20 years show all stars to be highly variable, including the massive
stars. Spectral fitting with thermal coronal emission line models reveals that
most sources show column densities of up to a few times $10^{22}\,$cm$^{-2}$
and high coronal temperatures of 10 to 90 MK. We observe a bifurcation of the
high temperature component where some stars show a high component of 40 MK,
while others show above 60 MK indicating heavy flaring activity. Some lines are
resolved with Doppler broadening above our threshold of
$\sim200\;\mathrm{km}\;\mathrm{s}^{-1}$, up to
$500\;\mathrm{km}\;\mathrm{s}^{-1}$. This data set represents the largest
collection of HETGS high resolution X-ray spectra from young pre-MS stars in a
single star-forming region to date.
