‘The Large Hadron Collider, the Higgs particle, and where we stand now’

One of the principal objectives for the gigantic particle accelerator that has recently been brought into full operation on the French-Swiss border near Geneva, is the detection of a theoretically predicted elementary particle called the Higgs particle. In theory, every elementary particle with spin, like quarks, electrons and others, can only have mass if it interacts with this Higgs particle, which itself is spinless. But what parts of the theory will no longer stand up if the Higgs particle is not found? And if it is found, then what do we learn, and what are the next scientific landmarks for this machine?