Ancient Greeks philosopher Leucippus and his pupil Democritus first proposed the idea that all matter consisted of invisible "atomos," or atoms, as we know them today. They believed these atomos could be divided into smaller and smaller particles until they reached a point that they could no longer be divided. Although they couldn't see the particles, Leucippus and Democritus tapped into a fundamental truth about our existence: The universe is made up of atoms and these atoms are responsible for life on Earth.
After considerable research and experimentation, we now know that atoms can be divided into subatomic particles -- protons, neutrons and electrons. Held together by electromagnetic force, these are the building blocks of all matter. Advances in technology, namely particle accelerators, also known as atom smashers, have enabled scientists to break subatomic particles down to even smaller pieces, some in existence for mere seconds. Subatomic particles have two classifications -- elementary and composite. Lucky for us, the names of categories can go a long way in helping us understand their structure. Elementary subatomic particles, like quarks, cannot be divided into simpler particles. Composite subatomic particles, like hadrons, can. All subatomic particles share a fundamental property: They have "intrinsic angular momentum," or spin. This means they rotate in one direction, just like a planet. Oddly enough, this fundamental property is present even when the particle isn't moving. It's this spin that makes all the difference.
Take a dive into the infinite and learn a little more about the world around us.