1. General
Point position can be expressed in relative or absolute terms.
a. Relative position
A relative position is the either the (a) length and direction, or, (b) latitude and departure between two points.
Give the adjusted traverse of Figure F1:
Figure F1 Adjusted Loop Traverse 
Lengths and directions around a traverse define the relative locations of successive traverse points.
Point B is 472.72 feet from point A at a bearing of S 68°05'27"W.
Point C is 216.12 feet from point B at a bearing of N 19°46'15"W.
In terms of latitudes and departures:
Point B is 176.39 feet South and 438.57 feet West of point A.
Point C is 203.38 feet North and 73.10 feet West of point B.
Where is point C relative to point A? Because the two points are not directly connected on the traverse, it requires a little more computing.
Lat A to C: [472.72 ft x cos(68°05'27") + 216.12 ft x cos(19°46'15")] = +26.99 ft
Dep A to C: [472.72 ft x sin(68°05'27")  216.12 ft x sin(19°46'15")] = 511.68 ft
Point C is 28.99 ft North and 511.68 ft West of point A. We could compute the lats and deps through point D instead of point B  the distances from point A to point C would be the same.
b. Absolute Position
An absolute position is a distance from a datum. In the case of a traverse point, two horizontal lines serve as the data. One line corresponds with the meridian, the other is perpendicular to it, Figure F2.
Figure F2 Horizontal Datum 
The meridional line is called either the Y or North (N) axis; the other the X or East (E) axis.
A point position is expressed as a coordinate pair are represent perpendicular distances from the two axes.
For example:
In terms of an X and Y system, Figure F3, the coordinates of point P are X=225.64' and Y=320.95'  
Figure F3 X and Y System 

In terms of an North and East system, Figure F4, the coordinates of point P are E=225.64' and N=320.95' 

Figure F4 North and East System 
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