Sol-gel preparation is a particularly powerful technique to control the intimacy of molecular-scale mixing in mixed oxides. This single property would explain why this technique is used in such wide number of applications. Further to purely inorganic gels, organically modified metal oxide polymers represent hybrid systems in which several precursor types are combined. Some metal-hybrid products have been developed with unique properties by combining alkoxide compounds with alkyl-substituted and organofunctional alkoxides. In principle such hybrid systems allow an unlimited number of chemical and structural modifications to be performed. Choice of specific precursors may be carried out on the basis of solubility or the thermal stability of the organofunctional substituents.

All these surface and bulk phenomena happening in gels, which endow them and those materials evolved from them, can not be understood without the use of different and diverse spectroscopic methods. This paper presents uses and applications of methods such as: Fourier Transformed Infrared Spectroscopy (FTIR), Ultra-Violet-Visible Spectroscopy (UV-Vis), Atomic Force Microscopy (AFM), Scanning Tunnelling Electron Microscopy (STM), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Electronic Spin resonance (ESR), Nuclear Magnetic Resonance (NMR), X-ray Diffraction Spectroscopy (XRD), Neutron Diffraction Spectroscopy (NDS), Differential Scanning Calorimetry (DSC), Thermal Gravimetric Analysis (TGA), Raman, Auger Electronic Spectroscopy (AES), X-ray Photon Spectroscopy (XPS), Mossbauer Spectroscopy and Small Angle X-ray Spectroscopy (SAXS), in sol-gel made materials. As they may explain some characteristics of such materials and why they awake the interest of many scientists.