Physicists are hunting for an elusive particle that would reveal the presence of a new kind of field that permeates all of reality. Finding that Higgs field will give us a more complete understanding about how the universe works Most people think they know what ma** is, but they understand only part of the story. For instance, an elephant is clearly bulkier and weighs more than an ant. Even in the absence of gravity, the elephant would have greater ma**—it would be harder to push and set in motion. Obviously the elephant is more ma**ive because it is made of many more atoms than the ant is, but what determines the ma**es of the individual atoms? What about the elementary particles that make up the atoms—what determines their ma**es? Indeed, why do they even have ma**? We see that the problem of ma** has two independent aspects. First, we need to learn how ma** arises at all. It turns out ma** results from at least three different mechanisms, which I will describe below. A key player in physicists' tentative theories about ma** is a new kind of field that permeates all of reality, called the Higgs field. Elementary particle ma**es are thought to come about from the interaction with the Higgs field. If the Higgs field exists, theory demands that it have an a**ociated particle, the Higgs boson. Using particle accelerators, scientists are now hunting for the Higgs