Rally point (terminology)
From Halopedia, the Halo wiki
Rally points are a mechanic in the Halo games.
First-person shooter
In the Halo first-person shooter games, rally points are featured in the campaigns from Halo 3 onward to allow the player to start a given level from the main menu at a select point. These can be used to let players easily experience select encounters or moments without needing to replay the entire level from the beginning. Rally points are typically named according to the NATO phonetic alphabet, with each level having around 1-3 rally points depending on its length. Depending on the rally point chosen the player may spawn with different weapons and equipment.
Rally points were introduced in Halo 3, and have since gone on to be used in Halo: Reach, Halo 4, and Halo: Campaign Evolved. They are also available for use in Halo: The Master Chief Collection, which additionally added rally points for levels in Halo 3: ODST that were not in the original Xbox 360 release of the game.
In the original Xbox 360 releases of Halo 3, Reach, and Halo 4, the mission start was not a rally point, with Rally Point Alpha instead the first rally point after the start. In the Master Chief Collection this was changed in all supported games so that the mission start is Rally Point Alpha; accordingly, all rally points were renamed so that what was previously Alpha and Bravo became Bravo and Charlie, respectively.
Real-time strategy
In the Halo Wars real-time strategy games, rally points serve a different purpose than their FPS counterparts. In both Halo Wars and Halo Wars 2, rally points serve as locations on the map which the player's units will automatically travel to once spawned. Rally points come in two types: Base Rally Points and Global Rally Points. Base Rally Points can be set by interacting with the HQ structure at any given Socket Base, and when placed, all units spawned at that base will travel to the rally point. Base Rally Points can also be used from any minibase or Elephant. Global Rally Points can be accessed from the leader power menu, and when placed override all Base Rally Points.