It's tough to think of a time before “Halo.” It was a genre-defining game and an experience that catapulted the Xbox and Microsoft into gaming legend. The first-person shooter featured intuitive controls, state-of-the-art graphics, and innovative gameplay. Many may forget, however, that it wasn't shown off at some Microsoft conference or E3 booth—it was announced by Steve Jobs at 1999's Macworld as an exclusive Mac title.
Bungie was still the driving name behind the title, gaining notoriety for “Marathon,”their popular first-person shooter series that were the three best games on the Mac in the 1990s. The development for “Halo” began behind closed doors and came out with one of the most impressive reveals of all time with huge maps and impressive lighting effects. So impressive, in fact, that Microsoft couldn't help but snatch Bungie away and make “Halo” their flagship game on their new console.
The game was originally supposed to be a third-person action game with highlights on online play. The game evolved into first-person, something Bungie knows a bit about, and the online features were dropped to maintain the needs of the console market. One thing that wasn't touched from the original reveal to the final release: The amazingly haunting score that we all remember to this day.