O2S has a plethora of types. These types are used by all aspects of the O2S system in specifications. Furthermore, all runtime objects are identified by a type so that the object may be inspected, shared between machines, reconstructed when necessary.
| Type | Description |
|---|---|
| http://o2s.lcs.mit.edu/specs/rtypes/Person.xml | A Person represents an O2S user object. |
| http://o2s.lcs.mit.edu/specs/rtypes/RTypeObject.xml | RTypes: Platform-independent, portable restricted types for O2S resourcesTranslate the specified value (which must be an rtype) to a Python objectcapable of being transmitted via XML-RPC and decoded at the far end ofthe connection to an appropriate representation. |
| http://o2s.lcs.mit.edu/specs/rtypes/defined_rtype.xml | A defined_rtype is a dict whose fields comform to a particular template. |
| http://o2s.lcs.mit.edu/specs/rtypes/dict.xml | A structured type mapping names to typed values. |
| http://o2s.lcs.mit.edu/specs/rtypes/double.xml | A 64-bit real number. |
| http://o2s.lcs.mit.edu/specs/rtypes/int.xml | A signed 32-bit integer. |
| http://o2s.lcs.mit.edu/specs/rtypes/list.xml | A finite sequence of rtype instances. |
| http://o2s.lcs.mit.edu/specs/rtypes/none.xml | A null type. |
| http://o2s.lcs.mit.edu/specs/rtypes/resource.xml | A resource is an O2S object. |
| http://o2s.lcs.mit.edu/specs/rtypes/rtype.xml | A rtype is any O2S data type. |
| http://o2s.lcs.mit.edu/specs/rtypes/string.xml | A string of ASCII characters. |