CERN was founded in 1954 as one of Europe’s first joint ventures, bringing specialists from twelve Member States together to pursue a common dream. Established on the Franco-Swiss border near Geneva, it has become a shining example of successful international scientific collaboration. Today, CERN has 21 Member States, and additional nations from around the globe also contribute to and participate in its research programme in various ways. CERN is a European laboratory for the world.

CERN’s business is fundamental physics, finding out what the Universe is made of and how it works. The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions. By studying what happens when particles collide, physicists learn about the laws underlying the evolution of the Universe.

CERN’s flagship is the Large Hadron Collider (LHC), the particle accelerator that provides the highest particle energies ever achieved in the laboratory. The energy density generated in its 13 TeV proton–proton collisions is similar to that existing a few instants after the Big Bang. Recreating such conditions is a tremendous way to look back to the birth of the Universe; it provides the only way to do experiments to find answers to very fundamental questions concerning, for example, the origin of mass, the nature of dark matter, and the balance of matter and antimatter in the Universe.

The LHC also accelerates beams of lead ions to energies never reached before. In these collisions, a state of matter in which quarks and gluons, which are otherwise confined in more complex particles, is set free, giving birth to the ‘quark–gluon plasma’: matter as it would have been in the first instants of the Universe’s existence.

Four large detectors, together with three smaller ones, record the particles produced in the LHC’s collisions. The processing and analysis of the data produced by these detectors presents a huge computing challenge. The Worldwide LHC Computing Grid harnesses distributed computing resources for physicists in institutes around the world to make the most of the rich harvest of physics available at the LHC. Altogether, CERN’s research programme involves some 12,000 researchers from over 500 institutes in more than 100 countries.