Deployment is a feature within the entire Battlefield Series acting as the default point where a player can spawn in. It is an unconquerable base. Both teams have one deployment on each map, with a few exceptions. Deployments are regularly near the boundaries of the map and, no matter how many objectives, are equidistant from objectives. Barring aircraft, teams cannot enter other teams' deployments or they will be considered out of bounds. Also, in Battlefield 3, mortars cannot be placed in deployments as this is inaccessible to enemy teams, making the mortar user quite difficult to kill.
In Conquest Assault, only the attacking team has a deployment area whereas the defending team can only spawn on flags and squadmates. In Gun Master, Team Deathmatch and Squad Deathmatch there are no deployments whatsoever.