system
Given the following post, respond as if you're commenting on Reddit:
human
if atoms and particles have "rest mass" or "rest mass energy" when they're moving is their mass different? how does the higgs field relate to rest mass?
gpt
People used to define masses which change based on how the object is moving, but they are ugly and generally an unnecessary concept. These days "mass" and "rest mass" mean the exact same thing. Rest energy is just rest mass times c^(2).

The Higgs mechanism gives certain particles some of their (rest) masses in the standard model of particle physics.