UP

Up (u): The lightest quark with a charge of +2/3

Mass: ~2.2 MeV/c² (very light)
Stable as part of nucleons (protons/neutrons)
Forms: Protons (uud), Neutrons (udd)
Interacts via: Strong, weak, electromagnetic, and gravitational forces
Decay: Doesn’t decay on its own (confined in stable particles)