Halo: Combat Evolved is a 2001 first-person shooter video game developed by Bungie and published by Microsoft Game Studios for the Xbox. It was released as a launch game for Microsoft's Xbox video game console on November 15, 2001. The game was ported to Microsoft Windows and Mac OS X in 2003

Halo 2 is a 2004 first-person shooter game developed by Bungie and published by Microsoft Game Studios for the Xbox console. Halo 2 is the second installment in the Halo franchise and the sequel to 2001's critically acclaimed Halo: Combat Evolved

Halo 3 is a 2007 first-person shooter video game developed by Bungie for the Xbox 360 console. The third installment in the Halo franchise, the game concludes the story arc begun in 2001's Halo: Combat Evolved and continued in 2004's Halo 2.

Halo 3: ODST is a 2009 first-person shooter game developed by Bungie and published by Microsoft Game Studios. The fourth installment in the Halo franchise as a side game, it was released on the Xbox 360 in September 2009.

Halo: Reach is a 2010 first-person shooter video game developed by Bungie and published by Microsoft Game Studios, originally for the Xbox 360. The fifth installment in the Halo series and a direct prequel to Halo: Combat Evolved, Reach was released worldwide in September 2010.

Halo 4 is a 2012 first-person shooter video game developed by 343 Industries and published by Microsoft Studios for the Xbox 360 video game console.

Halo 5: Guardians is a 2015 first-person shooter video game developed by 343 Industries, published by Microsoft Studios, and released worldwide for the Xbox One game console on October 27, 2015.

Halo Infinite is a 2021 first-person shooter game developed by 343 Industries and published by Xbox Game Studios. It is the sixth mainline entry in the Halo series, following Halo 5: Guardians.