Dirac fermions refer to particles governed by the Dirac equation, exhibiting specific quantum behaviors dictated by this equation. These fermions have intrinsic spin-1/2 and follow Fermi-Dirac statistics. Dirac fermions include electrons as they conform to the behavior described by the Dirac equation, accounting for their relativistic effects and spin. In condensed matter physics, materials like graphene and topological insulators host quasi-particles that behave akin to relativistic Dirac fermions due to their peculiar energy-momentum relationships. The unique electronic properties of these materials arise from the presence of Dirac-like excitations, leading to phenomena such as high carrier mobility or unusual electronic transport properties. Understanding and manipulating Dirac fermions in different systems offer insights into exotic quantum behaviors and pave the way for potential technological advancements in fields like electronics, spintronics, and quantum computing.