The term 'Ring of Radiance' is often used to refer to the HALO, a four-letter word. The HALO is a series of science fiction first-person shooter video games developed by Bungie and published by Microsoft Game Studios. It is one of the most successful video game franchises in history, selling over 65 million copies worldwide. The HALO series centers around an interstellar war between humanity and a theocratic alliance of aliens known as the Covenant. The HALO Ring is a powerful weapon that can be used to destroy entire planets. It is also a symbol of hope and protection for humanity.