Don Tuite wrote:
Crudely, your bearing is what your compass says at any given time.
Your course is your track over the ground.

You know, I always thought "bearing" was always relative. For example, if
someone tells me a target is at bearing 90 degrees I always know to look
out over my right shoulder and if they tell me I have a Klingon warship
bearing 180 I know I have a Klingon directly aft - whether I'm traveling
north, south, east, west, up, or down.

But it appears that in navigation the zero degree reference direction is
generally understood to be magnetic north unless context states otherwise.
Here's the Wikipedia info which seems to match your explanation:

http://en.wikipedia.org/wiki/Course_(navigation)
http://en.wikipedia.org/wiki/Bearing_%28navigation%29