The term Acceleration refers to the time required from the moment a movement is set into motion by a given key until the movement reaches full velocity (or until the movement stops after the key is released). This lets you create realistic start and stop movements for the camera. A minimum value of 1 will turn this effect off and the camera will start and stop abruptly. The higher the value the more sluggish the camera will react.
Acceleration can be set for the following properties:
Banking Velocity / Rotation Velocity
These settings let you define various speeds independently of one another:
Use this setting to define the speed sensitivity of the mouse for interactive control (changing the angle of view - left, right, up, down). Higher values require less movement of the mouse to achieve a greater view change.