Particle collisions occur when two or more subatomic particles, such as electrons or protons, come into contact with each other at high speeds. These interactions can produce new particles and help scientists understand the fundamental forces of nature. Particle collisions are often studied in large facilities like the Large Hadron Collider, where particles are accelerated to nearly the speed of light. The results of these collisions can reveal important information about the structure of matter and the universe. By analyzing the particles produced in these events, researchers can test theories in particle physics and explore concepts like dark matter and the Higgs boson.