 Titanium dioxide, TiO2, nanofluids have been widely studied due to their unique thermal and electrical properties. Various synthesis techniques have been developed to prepare TiO2 nanofluids, including single-step and two-step methods. In nature, TiO2 exists in three crystal forms, anatase, brucite, and rutile. These forms are not commonly used in heat transfer applications, making it difficult to develop stable and cost-effective nanofluids. Researchers have focused on producing nanosized solid particles by using various techniques, such as mechanical milling, sol, gel, hydrothermal, and chemical vapor deposition, CVD, before dispersing them into base fluids. The particle size and cost of the heat transfer device depend on the working fluid's properties, so scientists have made great efforts to formulate stable and cost-effective nanofluids with enhanced thermophysical properties. This article was authored by Hafeez Muhammad Ali, Hamza Babur, Tayyab Raza Shah, and others.