Directional well drilling is a process that controls the drilling direction in a well. Directional well driller's main body is couplable to a drill string, and a nose tubing that is movably mounted by a universal joint in the main body. A collar with a bore engages in a cam-like manner with an extension of the nose tubing on the drill string side of the universal joint. The collar is movable longitudinally to control the magnitude of the nose tubing, and circumferentially to control the azimuth. The nose tubing is aligned on both sides of the universal joint and the bore of the collar is angled relative to the main axis of the main body. The collar may be hydraulically or electrically controlled.