'If our ideas about the Higgs boson turn out to be correct, then everything we see is a kind of window dressing based on an underlying fabric of reality in which we shouldn't exist. The particles that make us up – which bind together to form protons, neutrons, nuclei and ultimately atoms – have mass. Without the Higgs, these particles would be massless, like photons.
We all know from our own experience that how heavy something feels depends on where it is located. For example, objects that are heavy on land appear lighter in water. Similarly, if you try to push a spoon through treacle it appears heavier than if you push it through air.
The standard model of particle physics implies that there is a "Higgs field" that permeates all space. This field interacts with particles, and does so with varying strengths. Particles that interact more strongly experience more resistance to their motion and appear heavier. Some particles, such as photons, do not interact with the field at all and remain massless.
In this way, the mass of everything is determined by the existence of the field, and mass is an accident of our circumstances because we exist in a universe in which such a background field happens to have arisen.' Lawrence Krauss