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We present here our results of the temporal and spectral analysis of a sampleof 52 bright and hard gamma-ray bursts (GRBs) observed with the Fermi Gamma-rayBurst Monitor (GBM) during its first year of operation (July 2008-July 2009).Our sample was selected from a total of 253 GBM GRBs based on each event peakcount rate measured between 0.2 and 40MeV. The final sample comprised 34 longand 18 short GRBs. These numbers show that the GBM sample contains a muchlarger fraction of short GRBs, than the CGRO/BATSE data set, which we explainas the result of our (different) selection criteria and the improved GBMtrigger algorithms, which favor collection of short, bright GRBs over BATSE. Afirst by-product of our selection methodology is the determination of adetection threshold from the GBM data alone, above which GRBs most likely willbe detected in the MeV/GeV range with the Large Area Telescope (LAT) onboardFermi. This predictor will be very useful for future multiwavelength GRB followups with ground and space based observatories. Further we have estimated theburst durations up to 10MeV and for the first time expanded the duration-energyrelationship in the GRB light curves to high energies. We confirm that GRBdurations decline with energy as a power law with index approximately -0.4, aswas found earlier with the BATSE data and we also notice evidence of a possiblecutoff or break at higher energies. Finally, we performed time-integratedspectral analysis of all 52 bursts and compared their spectral parameters withthose obtained with the larger data sample of the BATSE data. We find that thetwo parameter data sets are similar and confirm that short GRBs are in generalharder than longer ones.

First-year Results of Broadband Spectroscopy of the Brightest Fermi-GBM Gamma-Ray Bursts