The string of digits to the left of the (in a short format ) or to the left of the (in a long format ) is referred to as the item-identifier.

These values are available to uniquely identify an individual entity within the specified partition or namespace. The same item-identifier can be allocated in each partition of each namespace as the is rendered unique by the and the For components in the of item-identifiers will usually be issued in the arbitrary order in which components are added to However, due to management of the editing process the sequence of issued item-identifiers may be discontinuous.

CAUTION:

In all cases, the value of an item-identifier on its own is meaningless. The only way to determine the meaning of an  is by looking up the complete value in an appropriate distribution file.