Hundreds of millions of collisions per second -- Detectors collecting data to analyse 24/7 : the LHC and its experiements generate millions of gigabytes of data. The Computing Grid, a huge, worldwide network of computers was invented to manage, process and store these phenomenal volumes of data. How does it work? Who uses it? What is its performance since the LHC started up nearly two years ago? What are its other applications outside particle physics? We're going to review all this with Oliver Keeble, Computing engineer at CERN who works on the computing Grid.