Casson is a term that can refer to various subjects, but it is often associated with the mathematician Andrew Casson, known for his contributions to the field of topology. He developed the Casson invariant, a mathematical tool used to study 3-manifolds, which are three-dimensional spaces that can be shaped in various ways. This invariant helps classify these spaces based on their properties. In addition to mathematics, "Casson" may also refer to Casson & Co., a company involved in various industries, including consulting and engineering. The name is used in different contexts, but its significance often lies in the contributions made by individuals or organizations bearing the name.