I'm not quite sure what you are looking for, Venture, but the common measures in space are:
The AU (astronomical unit) This is the distance from Earth to the Sun, 93 million miles or about 8 light-minutes.
The Light-Year, or the distance light travels in one year, at a speed of 186,000 miles per second.
The Parsec, a distance of about three and a quarter light years.
In space, things don't slow down, there is no friction from roads or air, so anything that moves will continue to move in a straight line until something stops it. Therefore spacecraft have to fire their drives to accelerate and fire them again to decelerate. The quickest method of travel is therefore to accelerate to the halfway point, then decelerate the other half to bring the ship to rest at its destination.
Also, if a ship is moving at 1 inch per turn, toward the top of the table (lets call it north) it will continue to move in a straight line at 1 inch per turn without any input from the drives.
This is called a 1 inch vector. Firing the drives with a 1 inch reverse thrust will bring it to rest. Or, a further 1 inch forward thrust will increase the movement vector to 2 inches per turn.
If the moving ship fires its drives with a 1 inch vector to the left (west) instead, this will be added to the existing movement vector, and instead of moving 1 inch forward, it will move about an inch and a half at an angle of 45 degrees to the left. (ie northwest) The exact movement can be found by placing two one-inch arrows (vectors) at right angles, and the actual movement of the ship completes the triangle.
From now on, the ship's movement vector will be 1.41 (ish) northwest, until the ship fires its drives again. You can fire the drives in any direction and at any thrust short of your maximum to move your ship where you want it. Just lay the tail of the thrust vector to the head of the existing movement vector and your new vector is found by completing the triangle.
Hope that helps. More if needed.