The point that the camera is looking from (the camera's position). The coordinates are defined in the camera's worldReference.
The angle with respect to the horizon (aka. "tilt"). A value of 0 points the camera towards the horizon (i.e. horizontally). -90 points the camera straight down towards the ground and +90 points the camera straight up, towards the sky.
A rotation around the camera's forward direction (aka "bank"). Negative angles bank the view left; positive angles bank the view right.
The angle with respect to the north direction (aka. "heading"). A value of 0 points the camera towards the North pole. The angle increases in clockwise direction (90 points east).
A LookFrom represents the position of a camera.
This allows you to reason about the camera in terms of a point that the camera is looking from (ie. the position of the camera itself), together with a yaw (angle from north direction), pitch (angle wrt. horizon) and roll.
These properties also have meaning in a 3D cartesian reference, even though such a reference is not georeferenced: The xy-plane takes on the role of the (local) Earth ground plane and the z axis points up.
A LookFrom is defined by the following properties: