The X, Y, Z Coordinate System.

·         AutoCAD uses points determine where an object is located.

·        There is an origin where it begins counting from. This point is (0,0). Every object is       
     located in relation to the origin.

·        If you were to draw a lone straight out to the right from the origin, this would be                      considered the positive-axis.

·        If you were to draw a line straight up, this would be the positive Y-axis.

·        When you are working with points, X always comes first. The other point shown is                 (-10,-5). This means that the point is 10 units in the negative X-axis (left) and 5 units in         the negative Y-axis (down).