This chapter provides an overview of holographic methods for condensed matter physics, focusing on the AdS/CFT correspondence. It begins by discussing the motivation for applying holographic techniques to condensed matter systems, highlighting the unique insights they can provide into strongly coupled field theories and the experimental realization of high-energy theoretical concepts. The chapter then delves into quantum criticality, presenting examples such as the Wilson-Fisher fixed point and spinon-emergent photon models, and their relevance to nonconventional superconductors. The discussion moves to applied AdS/CFT methodologies, exploring the geometries of scale-invariant theories and the role of the dynamical critical exponent \( z \). The chapter concludes with a detailed examination of the minimal structure required for an applicable AdS/CFT duality, emphasizing the importance of spacetime geometry and the emergence of scale invariance.This chapter provides an overview of holographic methods for condensed matter physics, focusing on the AdS/CFT correspondence. It begins by discussing the motivation for applying holographic techniques to condensed matter systems, highlighting the unique insights they can provide into strongly coupled field theories and the experimental realization of high-energy theoretical concepts. The chapter then delves into quantum criticality, presenting examples such as the Wilson-Fisher fixed point and spinon-emergent photon models, and their relevance to nonconventional superconductors. The discussion moves to applied AdS/CFT methodologies, exploring the geometries of scale-invariant theories and the role of the dynamical critical exponent \( z \). The chapter concludes with a detailed examination of the minimal structure required for an applicable AdS/CFT duality, emphasizing the importance of spacetime geometry and the emergence of scale invariance.