Compass ross
It shows you the direction your traveling so you don't get lost.
A compass does not point to the North Pole, it aligns itself with the lines of magnetic force at your location. In the Northern Hemisphere you are closer to the North Pole, so the strength from that direction is greater, and the compass "points north". In the Southern Hemisphere, similarly, the magnetic South Pole is closer, and the other end of the compass points to the south Pole. So far so good. But when you are close to either pole, the magnetic field dips into the earth - steeply at the Poles themselves. [Ordinary compasses are counterbalanced a little so the compass needle or card is approximately horizontal. The compass manufacturers divide the earth into five 'balance' zones.] So a dip compass is suspended between two pivots, and will indicate the steepness of the magnetic fields dip. It differs from an ordinary compass.
it tells you the direction ur going
A compass or a GPS system would do the trick. An altimeter will indicate whether you are maintaining, losing, or gaining altitude.
What property it uses depends on the type of compass. A magnetic compass uses magnetism. Some other compasses (which are more accurate) use the rotation of Earth itself.
You can detect it by watching a compass needle, if that's what you mean.
A compass.
That is called a magnetic compass.
A compass - can only indicate a direction to travel. A GPS receiver - can not only show you which direction to go, but how far away you are from your destination.
A compass - can only indicate a direction to travel. A GPS receiver - can not only show you which direction to go, but how far away you are from your destination.
correctly when on a north or south heading.