9.1 Introduction9.2 Liquid Crystal Phases9.3 Liquid Crystals Alignment9.4 Basic Electro-Optic Effects in Liquid Crystals9.5 Liquid Crystal Characteristic Lengths9.6 Liquid Crystals in Waveguides9.7 Liquid Crystals Combined with Nanoparticles and Nanostructures9.8 Future TrendsAcknowledgmentReferences