NIST SP 800-82 (Guide to ICS/OT Security)

NIST SP 800-82 is the dedicated federal guide to securing industrial control systems and operational technology, covering architecture, threats, risk management, and specific security controls tailored to OT's constraints (like the difficulty of patching systems that can't be taken offline). It's one of the most heavily cited references throughout this glossary. Revision 3, published in 2023, broadened and retitled the document from "Guide to Industrial Control Systems (ICS) Security" (Revision 2) to "Guide to Operational Technology (OT) Security," reflecting the industry's shift toward the broader OT terminology.