Difference between Geometry string and Master String

Question :

What is the difference between Geometry string (GC string) and Master String (MC string)?

Answer:

Master Strings : are 6D strings and are generated from an alignment. Each point on Master string has 6 dimensions : x, y, z, chainage, tangent bearing and radius of curve. Each Master string has an associated Geometry string.

Geometry String : has 12 dimensions and store information about an alignment, for example, the horizontal and the vertical tangent points of the strings. A geometry string contains all the information necessary to generate the master string.