Introduce the principal elements of a particle accelerator such as the Large Hadron Collider at CERN. A computer interactive developed for the Microcosm exhibition at CERN introducing the workings of a particle accelerator like the Large Hadron Collider. Users of the interactive discover how, for example, protons are accelerated using electromagnetic fields. They then put their knowledge to the test as they are asked to regulate the accelerating field to accelerate a proton before passing to the next stage. On successful completion of the 3 steps (acceleration, bending and focusing) collisions occur and data taking can commence.