Roy Smith wrote:
Track is the motion you are making over the ground. It is what a GPS shows.

So far, so good.

Bearing is the direction from you to someplace else. It can be absolute
(bearing 270 degrees) or relative (9 O'Clock).

Correct, but worth clarifying. An absolute bearing of 270 degees means
if you go due west, you will get there. A relative bearing of 270
degrees means that if you go exactly to your 9 O'clock you will get
there. Bearing is always relative to your heading (which way your nose
is pointed) rather than your track (which way you are actually going).

I would say that Course and Track mean the same thing. They both refer to
your motion over the ground.

They do both refer to your motion over the ground, but track refers to
the way you are actually going, and course refers to the way you are
supposed to be going. If you consistently fly a LOC with two dots out,
you will still get to the runway - you are tracking to the runway - but
you are off course (and converging on it) and your track and course are
differnent (if only by a degree or so).

In GPS terms, course is the purple line on the GPS. Track is the way
the little airplane is actually pointed. Or, in VOR terms, the course
is the selected radial. Just because the CDI is centered (meaning you
are on your course) does not mean you are actually on the correct track
(you might just be swinging through center).

Heading is what direction the nose of the plane is pointing. It's what you
read off your compass or DG. If there was no wind, Heading and Course
would be the same.

With no wind heading and track are the same, not heading and course.

This is what I meant by internalizing the differences. The moving map
allows you to get by most of the time without really understanding the
difference. The ADF forces you to understand the differences.

Michael