Quarks

Group: fermion

Quarks are elementary particles, fundamental constituents of matter. There are six different quarks, the most important ones are up and down, which form protons and neutrons. The other quarks are created in highly energetic processes, are heavier and only have short lifetimes. They transform into the two lighter quarks.
Quarks have a color charge. This is only named after colors for illustration purposes, it doesn't have anything to do with real colors. A quark can have the color charge red, blue or green, its antiparticle has antired (or cyan), antiblue (or yellow) or antigreen (or magenta). Particles aspire to have no color at all. This is achieved by building hadrons, combinations of quarks. Those made of three different colored quarks are baryons, those of quark and antiquark with opposite colors are mesons. In both cases, the resulting color charge is white (red+blue+green or e.g. blue+antiblue). Only the top isn't able to do this, because its lifetime is too short to form hadrons.
Combinations of quarks are kept together by the strong interaction, which is carried by gluons, that have a color charge, too.

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