Matter is composed of tiny particles known as atoms. Atoms are the basic building blocks of matter and consist of three primary subatomic particles: protons, neutrons, and electrons.
Protons are positively charged particles found in the nucleus of an atom, while neutrons are neutral particles that also reside in the nucleus. The nucleus is the central part of the atom, and these two particles (protons and neutrons) together are referred to as nucleons.
Electrons are negatively charged particles that orbit the nucleus in varying energy levels or shells. The presence and arrangement of these particles determine the chemical properties of the element.
To summarize, atoms, made up of protons, neutrons, and electrons, are the fundamental units of matter. Different elements are defined by the number of protons they contain, and the interactions between electrons of different atoms lead to the formation of molecules, further contributing to the diversity of matter we observe in the universe.