A hadron is a type of subatomic particle that is made up of quarks, which are fundamental particles. Hadrons are categorized into two main groups: baryons and mesons. Baryons, like protons and neutrons, consist of three quarks, while mesons are made of one quark and one antiquark. Hadrons are held together by the strong nuclear force, which is mediated by particles called gluons. Hadrons are essential components of atomic nuclei and play a crucial role in the structure of matter. They are studied in particle physics to understand the fundamental forces and particles that make up the universe. Experiments involving hadrons often take place in large facilities like particle accelerators, where scientists can observe their interactions and properties.