In recent times, the demand for electrical energy is increased to such an extent that the scientific research has to be focused on the development of materials that fulfil the growing demands of energy for efficient solid state lighting purposes and provide clean and green energy to mitigate the alarming effects of climate change. The ternary Indium Gallium Nitride (In x Ga 1-x N) alloys have emerged as the potential candidate for Solid State lighting as they inherent such attributes that make them capable for these applications. In this review, the attributes of In x Ga 1-x N alloys have been discussed. The dependence of bandgap and bowing parameter on the composition of In x Ga 1-x N alloys along with various techniques employed for the growth of these alloys in bulk and nanostructure forms have been reviewed. The recent advances in In x Ga 1-x N based nanostructures for Solid State lighting have also been extensively reviewed. The challenges that are to be overcome for potential use of In x Ga 1-x N alloys like phase segregation, unavailability of a suitable substrate, polarization and doping have been thoroughly highlighted. In the end, the conclusion and future scope of work on these wonderful classes of materials has been drawn.