Mesons are subatomic particles made up of one quark and one antiquark, which are types of elementary particles. They belong to the family of particles known as hadrons, which also includes baryons like protons and neutrons. Mesons are typically unstable and exist for a very short time before decaying into other particles. They play a crucial role in mediating the strong force that holds atomic nuclei together. There are various types of mesons, classified based on their properties such as mass and charge. Examples include the pion and the kaon. Mesons are important in particle physics and help scientists understand the fundamental forces and interactions that govern the behavior of matter in the universe.