Where to find comprehensive description of Special Use Airspaces (SUAs)?
The definition of Special Use Airspace according to Wikipedia are:


  Is an area designated for operations of a nature such that limitations may be imposed on aircraft not participating in those operations. Often these operations are of a military nature.


Types of SUA's


  restricted airspace, prohibited airspace, military operations areas (MOA) and temporary flight restriction.


Two relevant PDF documents:
https://www.faa.gov/documentLibrary/media/Order/7400.8SBasic.pdf

https://www.faasafety.gov/files/events/GL/GL05/2007/GL0515004/CH_3_Sec_4.pdf

Wikipedia link: https://en.wikipedia.org/wiki/Special_use_airspace