The Griess group is a finite group in the field of group theory, named after mathematician R. L. Griess Jr.. It is notable for being the smallest known example of a non-abelian simple group, which means it cannot be broken down into simpler groups. The Griess group has an order of 2^3 × 3^2 × 5 × 7, making it a complex structure with interesting properties. Discovered in the 1980s, the Griess group is also related to the theory of vertex operator algebras and has connections to string theory in physics. Its unique characteristics have made it a subject of study in both mathematics and theoretical physics, highlighting the interplay between these fields.