Describe errors in collections?

COLLECTION_IS_NULL:                You try to operate on an atomically null collection.

NO_DATA_FOUND:                        A subscript designates an element that was deleted, or a      nonexistent element of an associative array.

SUBSCRIPT_BEYOND_COUNT:   A subscript exceeds the number of elements in a collection.

SUBSCRIPT_OUTSIDE_LIMIT:      A subscript is outside the allowed range.

VALUE_ERROR:                             A subscript is null or not convertible to the key type. This exception might occur if the key is defined as a PLS_INTEGER range, and the subscript is outside this range.