This review summarizes the current knowledge on the use, advances, advantages, and limitations of various experimental techniques for the characterization of nanoparticles (NPs). The article discusses different characterization techniques, classifying them based on the concept or group of the technique, the information they provide, or the materials they are intended for. It describes the main characteristics of these techniques, their operating principles, and provides various examples of their use, often in a comparative manner, in relation to the property being studied. Nanoparticles have unique properties due to their high surface-to-volume ratio, including electronic, optical, and chemical properties, as well as differences in mechanical characteristics. These properties make NPs important for both academic research and technological applications. However, the characterization of NPs is challenging due to their small size, low quantity, and the need for precise and reliable methods. The review highlights the importance of combining different techniques to obtain a comprehensive understanding of NP properties. The article discusses various techniques for characterizing NPs, including X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), which includes extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES), and small-angle X-ray scattering (SAXS). These techniques provide information on the crystalline structure, elemental composition, and other physical properties of NPs. The review also discusses the advantages and limitations of each technique, emphasizing the need for a complementary approach to achieve accurate and reliable results. The review highlights the importance of using multiple techniques to characterize NPs, as each technique has its own strengths and limitations. For example, XRD is useful for determining crystalline structure, while SAXS is effective for determining particle size and shape. EXAFS is particularly useful for studying the local atomic structure and chemical bonding in NPs. The review also discusses the application of these techniques in various fields, including materials science, chemistry, and biology, and emphasizes the need for continued research and development to improve the characterization of NPs.This review summarizes the current knowledge on the use, advances, advantages, and limitations of various experimental techniques for the characterization of nanoparticles (NPs). The article discusses different characterization techniques, classifying them based on the concept or group of the technique, the information they provide, or the materials they are intended for. It describes the main characteristics of these techniques, their operating principles, and provides various examples of their use, often in a comparative manner, in relation to the property being studied. Nanoparticles have unique properties due to their high surface-to-volume ratio, including electronic, optical, and chemical properties, as well as differences in mechanical characteristics. These properties make NPs important for both academic research and technological applications. However, the characterization of NPs is challenging due to their small size, low quantity, and the need for precise and reliable methods. The review highlights the importance of combining different techniques to obtain a comprehensive understanding of NP properties. The article discusses various techniques for characterizing NPs, including X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), which includes extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES), and small-angle X-ray scattering (SAXS). These techniques provide information on the crystalline structure, elemental composition, and other physical properties of NPs. The review also discusses the advantages and limitations of each technique, emphasizing the need for a complementary approach to achieve accurate and reliable results. The review highlights the importance of using multiple techniques to characterize NPs, as each technique has its own strengths and limitations. For example, XRD is useful for determining crystalline structure, while SAXS is effective for determining particle size and shape. EXAFS is particularly useful for studying the local atomic structure and chemical bonding in NPs. The review also discusses the application of these techniques in various fields, including materials science, chemistry, and biology, and emphasizes the need for continued research and development to improve the characterization of NPs.