The ALICE experiment -- Nuclear collisons at the high-energy frontier at LHC

A Large Ion Collider Experiment (ALICE) is the dedicated experiment for studying nuclear collisions at the LHC. It will address the physics of QCD matter under extreme conditions of temperature and energy density. ALICE is an international collaboration of more than 1000 physicists and engineers from presently 105 institutions. First p+p collisions provided by LHC are expected at the end of this year. The current status of the ALICE experiment, its instrumentation and performance capabilities are presented. The ALICE physics potential is highlighted by discussing some selected examples scheduled for first p+p collisions, and subsequent Pb+Pb collisions.