Explore a comprehensive lecture on the unique beta (bcc) to omega (hexagonal) phase transition in this Foundation Day presentation by Srikumar Banerjee from the Homi Bhabha National Institute, Mumbai. Delve into the formation of the omega phase in Group 4 metals and various alloys, examining its occurrence as both an equilibrium and metastable phase. Investigate the transformation mechanism, including the periodic displacement of {222} planes in the parent bcc structure. Discover pre-transition effects, phonon softening, and recent high-resolution electron microscopy findings that provide deeper insights into this first-order transition. Cover topics such as order parameters, symmetry rules, continuous transitions, crystallography, diffraction patterns, phase diagrams, and chemical changes associated with omega formation.