Stannic oxide in its pure form is an n‐type wide‐bandgap semiconductor. Its electrical conduction results from the existence of point defects (native and foreign atoms) which act as donors or acceptors. Some unique properties of make the material useful for many applications. Therefore, increasing attention is being paid to studies on this oxide, especially on the methods of preparation, and its electrical and optical properties. The purpose of this work is to provide a general up‐to‐date review of the investigations carried out and to help identify important areas for further studies. This part is concerned with the preparation and defect structure of single crystals, sintered polycrystalline samples, and thin films. Parts II and III2 are reviews of the electrical and optical properties of materials.