This Manual is issued under the authority of DoD Directive 5000.59, "DoD Modeling and Simulation (M&S) Management," January 4, 1994. Its purpose is to prescribe a uniform glossary of modeling and simulation (M&S) terminology for use throughout the Department of Defense. In addition to the main glossary of terms, this Manual includes a list of M&S-related abbreviations, acronyms, and initials commonly used within the Department of Defense.