In the world of physics, everything is made up of fundamental building blocks known as atoms. Atoms are incredibly small, with diameters on the order of a few angstroms. They consist of three main subatomic particles: protons, neutrons, and electrons.

• Protons are positively charged particles found in the nucleus of an atom. They have a mass of approximately 1 atomic mass unit (u).

• Neutrons are electrically neutral particles also located in the nucleus. They have a mass similar to that of protons.

• Electrons are negatively charged particles that orbit the nucleus. They have negligible mass compared to protons and neutrons.

These subatomic particles are vital in understanding the nature of matter and the behavior of atoms. The discovery of these particles and their properties have paved the way for modern physics.