Commissioning and Performance of the CMS Detector

The Compact Muon Solenoid detector at the LHC accelerator was extensively tested and commissioned during the years 2008 and 2009 using cosmic muons and being prepared for collision data. With the LHC start-up and the first runs at 7 TeV in the years 2009 and 2010 CMS started to record its first collision events. This data have been used to perform detailed studies on the performance of the detector, ranging from the efficiency of the data taking to the study of the first observed mass resonances. In this process, the calibration and commissioning of CMS has shown to be well advanced, and the detector prepared for the first Standard Model measurements.