The biaxial nematic phase was predicted more than three decades ago and discovered in lyotropic liquid crystalline systems by Yu and Saupe in 1980. However, several attempts to invent and synthesize new thermotropic materials likely to form this phase did not succeed. Several reports of its discovery in the thermotropic materials have proven to be without merit. While investigating the structure of smectic phases in bent-core (or, banana) mesogens, we came across unusual diffraction pattern in their nematic phase. The experimental investigations that followed and modeling, have established their biaxial nature. Recently synthesized materials exhibit the existence of, both, the uniaxial and the biaxial nematic phase.