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=                               Hadron                               =
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                             Introduction
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In particle physics, a hadron  (, 'hadrós;' "stout, thick") is a
subatomic composite particle made of two or more quarks held together
by the strong force in a similar way as molecules are held together by
the electromagnetic force. Most of the mass of ordinary matter comes
from two hadrons, the proton and the neutron.

Hadrons are categorized into two families: baryons, made of an odd
number of quarks - usually three quarks - and mesons, made of an even