Adagietto contains all the nuts and bolts for core string writing - featuring Ensemble Strings from Adagio
Agitato is a specialty series designed to target the most sought after ensemble string articulations (ex. Williams Legato etc)
Adagio is the individual volumes (Violins, Violas, Cellos, and Basses) from Anthology Strings separated into individual instruments which contain Solo, Chamber, and Ensemble Instruments.
Anthology is ALL of the libraries in one convenient, super-polished, collection. New UI, new functionality etc.