  The Fermi Gamma-Ray Space Telescope has more than doubled the number of
Gamma-Ray Bursts (GRBs) detected above 100 MeV within its first year of
operation. Thanks to the very wide energy range covered by Fermi's Gamma-ray
Burst Monitor (GBM; 8 keV to 40 MeV) and Large Area Telescope (LAT; 25 MeV to
>300 GeV) it has measured the prompt GRB emission spectrum over an
unprecedentedly large energy range (from ~8 keV to ~30 GeV). Here I briefly
outline some highlights from Fermi GRB observations during its first ~1.5 yr of
operation, focusing on the prompt emission phase. Interesting new observations
are discussed along with some of their possible implications, including: (i)
What can we learn from the Fermi-LAT GRB detection rate, (ii) A limit on the
variation of the speed of light with photon energy (for the first time beyond
the Planck scale for a linear energy dependence from direct time of arrival
measurements), (iii) Lower-limits on the bulk Lorentz factor of the GRB outflow
(of ~1000 for the brightest Fermi LAT GRBs), (iv) The detection (or in other
cases, lack thereof) of a distinct spectral component at high (and sometimes
also at low) energies, and possible implications for the prompt GRB emission
mechanism, (v) The later onset (and longer duration) of the high-energy
emission (>100 MeV), compared to the low-energy (< ~1 MeV) emission, that is
seen in most Fermi-LAT GRBs.
