This review article comprises of detailed discussions about different types of thin-film coating techniques in which Indium-doped Tin Oxide (ITO) has been coated by various researchers across the world. Since, it is indispensable to incorporate the working of the coating processes to make ITO films for specific applications, working of each coating technique has also been explained in detail. This work provides a comprehensive details about the previously reported works on ITOs. The details include precursors used in the preparation of ITO substrates, electrical and optical properties of ITO, resistivity, transparency, growth rate and structure of the coated films, characterization techniques studies carried out for the ITO films. It was noted that the films coated by CVD technique had the highest transmission of 90-95%. Minimum resistivity of 0.7-12 × 10−4 Ωcm was obtained for Evaporation technique. This review article will provide a detailed discussion on used techniques for developing the ITO films for TCO applications and their applications.