Parallelism, perpendicularity, and angularity are considered GD&T functions that calculate the orientation of 2 features related to each other.
For more information on how to use these 3 functions, please see the attached method sheet. The method sheet is using Measure Q, but applies to Measure 10 as well.
Click here to download: GD&T Method Sheet
Keywords: angularity, parallelism, perpendicularity, Measure q