ISO/IEC 19773:2011 specifies small modules of data that can be used or reused in applications. These modules have been extracted from ISO/IEC 11179-3, ISO/IEC 19763, and OASIS EBXML, and have been refined further. These modules are intended to harmonize with current and future versions of the ISO/IEC 11179 series and the ISO/IEC 19763 series. These modules include: reference-or-literal (reflit) for on-demand choices of pointers or data; multitext, multistring, etc. for recording internationalized and localized data within the same structure; slots and slot arrays for standardized extensible data structures; internationalized contact data, including UPU postal addresses, ITU-T E.164 phone numbers, internet E-mail addresses, etc.; generalized model for context data based upon who-what-where-when-why-how (W5H); data structures for reified relationships and entity-person-groups. Conformity can be selected on a per-module basis.