explain orientation values?

[smore]

When investigating a particular object's pointOfView property, I see both the position coordinates and the orientation information, for example:

position: -0.6, 3.71, 0.3; orientation: (0.17, 0.28, 0.05) 0.94


Can someone tell me what the final value in the orientation information represents (i.e., the 0.94 above)?


Thanks!