space and air battle dimensions share a single frame shape. In the ground battle dimension, two different frames are used for the friendly (and assumed friendly) affiliations in order to distinguish between units and equipment. The SOF (special operations forces) are assigned their own battle dimension because they typically can operate across several domains (air, ground, sea surface and subsurface) in the course of a single mission; the frames are the same as for the ground (unit) battle dimension. The other battle dimension, finally, seems to be reserved for future use (there are no instances of its use as of 2525B Change 1). Status The status of a symbol refers to whether a warfighting object exists at the location identified (i.e., status is "present") or will in the future reside at that location (i.e., status is "planned, anticipated, suspected," or "on order"). Regardless of affiliation, present status is indicated by a solid line and planned status by a dashed line. The frame is solid or dashed, unless the symbol icon is unframed, in which case the icon itself is drawn dashed. Planned status cannot be shown if the symbol is an unframed filled icon. Icon placement The icon is the innermost part of a symbol which, when displayed, provides an abstract pictorial or alphanumeric representation of an operational object. The icon portrays the role or mission performed by the object. APP-6A distinguishes between icons that must be framed or unframed and icons where framing is optional. APP-6A defined a standard octagon boundary within each map symbol frame. This octagon is not actually shown when symbols are drawn or rendered but, with a few defined exceptions, all icons inside the frame would also fit inside these octagons. APP-6C modified some symbol frames from previous editions of the standard. From top to bottom, here is the symbol boundary shown inside the APP-6C frames of space elements, air elements, land units, land equipment and surface sea elements, and sub-surface sea elements. Unit symbols Unit icon modifiers Unit symbols can be used independently as well as in combinations. There are also some symbols that cannot appear by themselves, but can only be used to modify other unit symbols: Unit basic icons Land unit icons require a frame. Modified unit icons Some of the most common combinations are: Unit size indicators Above the unit symbol, a symbol representing the size of the unit can be