  Defined by Lord Kelvin as the science of measurement it is described a
fundamental fact of physics. The so called `natural' units represent the unique
system of units conveniently used in the realm of High Energy Physics. The
system of natural units is defined by the consistent providing of the
adimensional unit value to the velocity c of the eletromagnetic radiation in
the vacuum, related to the Maxwell classical electromagnetic theory and to the
special relativity theory, to the reduced Planck constant
$\hbar\equiv\frac{h}{2\pi}$ having the dimension of action, which is the
fundamental constant of the quantum mechanics as well as to the Boltzmann
constant $k_B$ which has the dimension of heat capacity, being the fundamental
constant associated to the statistical mechanics, $c=\hbar = k_B = 1$. Such
prescription is mandatory as we investigate the ultimate constituents of matter
and their dynamics, since the atoms, leptons and quarks up to the grand
unification, strings, superstrings, and the supergravity theories, as well as
the total unification of the interactions in the M-theory. The one-dimensional
character of this phenomenology is totally featured by the use of the natural
units, reflecting the fact that in order to be possible the investigation of
the fundamental constituents of matter it is being necessary the resolution of
lengths of the order of $10^{-16} cm$ or to reach energies of the order of at
least 1 TeV. The application of this system of natural units results
exceptionally adequate in the description of the Universe since the Planck
scale, up to the Hubble large scale expanding Universe, resulting in the
curious formation of the regular numerical clusters.
