Specialized Administration > Tailoring Business Objects > Object Initialization Rules Administration > Understanding Object Initialization Rules > Changing Versioning Schemes > Harvard Series Versioning Schemes
  
Harvard Series Versioning Schemes
A Harvard series is made up of one or more subseries and is typically depicted as a stream of values delimited by a period (for example, 1.1, A.B.A, 1.2.1.1, and so on).
There are four Harvard versioning schemes available for your use:
A standard alphabetic scheme
A standard integer scheme
A file-based scheme
A state-based scheme
The following sections provide details on the versioning schemes that are defined and the properties used to set up the schemes.