What is the smallest thing in the world?

The smallest thing in the world is a fundamental particle. There are two types of fundamental particles: quarks and leptons. Quarks are found inside protons and neutrons, which make up the nucleus of an atom, while leptons are particles that do not interact with the strong nuclear force.

Quarks and leptons are considered to be point-like particles, which means that they have no size. They are the building blocks of all matter in the universe, and they cannot be broken down any further.

However, it is important to note that while fundamental particles are considered to be the smallest things in the world, they still have properties such as mass, charge, and spin. These properties can be measured and studied using advanced technologies such as particle accelerators.