Marking classified information serves several purposes in the Department of Defense.

Classifying Quadrilaterals A quadrilateralis a polygon with four sides. The diagram shows properties of different types of quadrilaterals and how they are related. When identifying a quadrilateral, use the …

ING ORIGINALLY CLASSIFIED INFORMATION Original classification is an initial determination made by an original classification authority (OCA) that information requires, in the interest of national …

All original classification authorities must receive training in proper classification (including the avoidance of over-classification) and declassification as provided in this order and its implementing directives at …

“25X” with date or event, designating a duration of up to 50 years from the date of original classification,* when classifying information that clearly falls within an exemption from automatic declassification at …

Classification standards are public documents and should be available for review by anyone interested in their content. Copies of current standards must be maintained for use by those with responsibility …

Classifiers are responsible for assuring that information is appropriately classified and properly marked. The proper markings include declassification instructions.