EMCON — Emissions Control — is a military operational state in which a unit restricts or eliminates the use of electronic emissions to reduce its detectability. Radar off. Radio silent. Active sonar silent. The unit operates as if electronically invisible. What It Is Modern militaries emit constantly in normal operations: radar pulses sweep the horizon, radios carry voice and data traffic, jammers and electronic warfare systems radiate energy. All of this is detectable.

A FRAGO — Fragmentary Order — is a condensed military order that modifies or supplements a previously issued operation order (OPORD) without replacing it. It exists because combat operations change faster than the full order process can accommodate. What It Is Military operations are planned through a formal process that produces an OPORD — a complete, five-paragraph operation order covering situation, mission, execution, sustainment, and command and signal. OPORDs can run dozens of pages.

The Law of Armed Conflict (LOAC) and Rules of Engagement (ROE) both govern how military forces may use force, but they operate at different levels of authority and with different purposes. LOAC is the floor — the minimum standard set by international law that cannot be waived. ROE is the operational framework layered on top, which can only restrict, never expand, what LOAC allows. What They Are LOAC — Law of Armed Conflict

MOPP — Mission Oriented Protective Posture — is the U.S. military system for specifying how much chemical, biological, radiological, and nuclear (CBRN) protective equipment personnel must wear in a given threat environment. MOPP levels run from 0 to 4, with each level adding another layer of protection and another layer of heat stress. What It Is MOPP is a tiered readiness framework, not a single piece of equipment. It describes how much of the available CBRN protective gear must be worn, allowing commanders to calibrate the trade-off between protection and operational effectiveness.

ORBAT — Order of Battle — is a structured accounting of a military force’s composition, organization, and disposition. It answers the essential intelligence questions: what units exist, how are they organized, where are they, and what can they do? What It Is An ORBAT is both a document and an analytical framework. At its most basic, it is a hierarchical list: army groups contain armies, armies contain corps, corps contain divisions, divisions contain brigades, brigades contain battalions, and so on.

A SITREP (Situation Report) and a SPOTREP (Spot Report) are both military reporting formats, but they serve fundamentally different purposes and operate on different timelines. Confusing them produces either stale information delivered promptly or current information buried in unnecessary structure. What They Are SITREP — Situation Report A SITREP is a periodic, comprehensive summary of the current operational situation. It is scheduled, structured, and cumulative. A unit submits SITREPs at fixed intervals — every six hours, every twelve hours, every twenty-four hours — as specified in the operation order.