A management class definition contains both descriptive and storage-related information. To identify and refer to your management classes, you assign each one a unique name that contains from one to eight alphanumeric characters. Each management class definition maintains an owner ID that identifies the storage administrator who originally created or last modified the management class. The owner ID is a z/OS® user ID on the ISMF Management Class List in column 19-Last Modified Userid. Also, each management class contains an optional 120 character description field for describing its contents.