There are several ways to plot a course in 3-dimensional space. One way is to provide a flight vector specified as an azimuth/elevation relative to another flight vector (usually the vessel's current orientation). This method, using the spherical coordinate system, gives the azimuth and elevation values as angles relative to another vector. These angles, the "bearing" and "mark", respectively, are given in degrees, with 360 degrees being equal to one full rotation.