A descriptor in Symbian OS is a text string. There is a library of descriptor classes incorporating the usual string manipulation methods. Descriptors come in two main types, 8 bit and 16 bit. An 8 bit descriptor stores ASCII text or binary data, a 16 bit descriptor stores Unicode text.
Descriptor is also being used in an MRP program called DBA Next Generation. In this program a descriptor is a bill of material item that is a non-stock item like labor.
In the Python programming language a descriptor is "an object attribute with 'binding behavior', one whose attribute access has been overridden by methods in the descriptor protocol." For example a descriptor can be used to prevent setting the radius attribute of an object representing a circle to a negative value or to log all access or changes to a specific attribute.