Cholesteric liquid crystals (CLC) have recently attracted enormous interest in the development of soft materials due to their unique ability to change their refractive index, tuning of optical density states, selective and specific diffraction wavelengths, formation of supramolecular helical architecture, self-organized pitch gradient with nanostructures, non-uniform distribution of pitch gradient etc. present chapter focuses on the physical and optical properties of CLC with broad refection characteristics, formation of CLC with chiral and achiral dopants, their florescence characteristics, broad range of optical applications, wide range of device architecture used in the modulation of optical active intelligent materials etc. The chapter also illustrates the formation of CLC emulsions their basic device architecture, illustration of the optical microscopy, and in the applications of optical anti-counterfeiting, modifiable optical signals, response to the external circuit etc. The chapter also covers the synthesis of CLC, their basic physical and chemical characteristics, fluorescent nature, polymer stabilized CLC, flexibility in the molecular design, temperature responsive CLC, their basic optical device architecture. The chapter also enlighten briefly about the CLC integrated system used in the various optical and electrical applications.