OMDoc is an XML application, organized into ten modules,
| MOBJ | Math Objects | Mathematical Formulae in OpenMath, MathML or legacy formats. |
| DC | Dublin Core Metadata | in Dublin Core |
| CC | Creative Commons Metadata | licensing metadata in CC format |
| ST | Statements | i.e. Definitions, Theorems, Axioms, Examples, etc, and simple theories with inheritance |
| PF | Proofs | as proof objects or structured proofs from hypotheses |
| ADT | Abstract Data Types | for structured definition of inductively defined sets |
| CTH | Complex Theories | To add inheritance via translations, theory inclusions. |
| DG | Development Graphs | An infrastructure for the management of theory change. |
| PRES | Presentation | OMDoc allows the user to specify notations for content mathematical objects. |
| EXT | Web Extensions | to be able to specify applets, private (non-XML) data, etc. |
| QUIZ | Exercises/Quiz | to make OMDoc a viable format for educational and course materials |