Deformation quantization is a mathematical framework that aims to reconcile classical mechanics with quantum mechanics. It involves modifying classical observables, represented as functions on a phase space, into non-commutative operators in a way that preserves the structure of the original theory. This process allows for the transition from classical to quantum systems while maintaining certain properties of the classical phase space. The concept was developed in the context of mathematical physics and is closely related to symplectic geometry and operator algebras. It provides a systematic approach to understanding how classical systems can be "deformed" into their quantum counterparts, facilitating the study of quantum field theories and other advanced topics in quantum mechanics.