"Physics is the science of nature"

Physicists study the behavior and properties of matter within a huge range,

from the sub-nuclear particles from which all ordinary matter
is made, nuclear and particle physics.
to the behavior of the material Universe as a whole ( cosmology).

"Nuclear and Particle Physics"
Over the last century physicists have discovered that molecules are made of atoms. In 1911, E. Rutherford showed that an atom is made up of a nucleus and electrons, i.e. a small, hard nucleus surrounded by electrons - the birth of nuclear physics. Later it was discovered that the nucleus is made of nucleons (protons and neutrons) - the beginning of particle physics. In the last 40 years, we have discovered that even nucleons themselves have structure; they are made of more fundamental particles, the quarks, which were discovered, in 1968, at Stanford Linear Accelerator Center ( SLAC). However, we still do not know whether quarks are structureless, or made of more fundamental particles. If current theoretical physics models are correct, then there are as yet undiscovered new particles, and that the search for them is the most important endeavors in all of science.