Jet Physics in the ATLAS experiment at LHC

Jet physics represents a powerful tool to investigate the properties of quark and 5 gluon interactions. With the advent of LHC, these studies have been possible at an 6 energy never investigated before. In this paper we review the main characteristics 7 of jets measured by the ATLAS experiment in proton-proton collisions at energies 8 of 7 and 8 TeV. The experimental results are compared with the predictions of the 9 Quantum Chromodymamins, QCD, the standard theory of quark-gluon interac- 10 tions. A good agreement is found between the data and the QCD predictions. The 11 jet mesurements provide also a clue in the search for new physics: a few example 12 will be given of search for excited quarks and supersymmetric particles.