The use of X-rays for material analysis has revolutionized our understanding of various materials, providing invaluable insights. This chapter delves into X-ray applications, including XRD, XRF, XPS, AES, and SIMS. It begins with X-ray production and then details the principles, operations, and applications of these techniques, offering deep insights into material properties. XRD is vital for deciphering solid crystalline structures and atomic arrangements, revealing lattice spacing, symmetry, and phases. XRF excels in elemental analysis, offering both qualitative and quantitative results by generating distinctive fluorescent X-rays when X-rays interact with a sample. XPS focus on surface analysis, determining elemental composition and chemical states. SIMS enables high-sensitivity elemental and isotopic analysis of surfaces. These techniques find diverse applications. This chapter enhances readers' understanding of these techniques, helping them choose the right approach for material characterization, fostering scientific progress and technological innovation.