where do most comets come from

Most comets come from two primary regions in the outer solar system: the Oort Cloud and the Kuiper Belt. Long-period comets, which have orbits longer than 200 years, typically originate from the distant Oort Cloud, a vast spherical shell of icy bodies surrounding the solar system far beyond Neptune. Short- period comets, with orbits less than 200 years, usually come from the Kuiper Belt, a disc-shaped region of icy objects located beyond Neptune's orbit. The Oort Cloud is thought to contain around a trillion comets and extends from about 3,000 to 100,000 astronomical units (AU) from the Sun, while the Kuiper Belt lies roughly between 30 and 50 AU. Some comets may also originate from the scattered disc, a dynamically active region linked to the Kuiper Belt. The distinction in origin explains differences in the orbital characteristics of comets observed in the inner solar system.