| Namespace | Resource Type Described, if any | Current canonical, resolvable location | Prior versions that may still exist and appear in registries |
| vr | Resource | http://www.ivoa.net/xml/VOResource/v1.0 | |
| ri | Resource | http://www.ivoa.net/xml/RegistryInterface/v1.0 | |
| vs | DataService | http://www.ivoa.net/xml/VODataService/v1.1 | <a target="_blank" href="http://www.ivoa.net/xml/VODataService/v1.0">http://www.ivoa.net/xml/VODataService/v1.0</a> |
| uws | (not a resource type: Universal Worker Service) | http://www.ivoa.net/xml/UWS/v1.0 | |
| cap | (not a resource type: VOSI capability) | 'http://www.ivoa.net/xml/VOSICapabilities/v1.0 | |
| stc | (not a resource type) | http://www.ivoa.net/xml/STC/stc-v1.30.xsd | |
| oai | (not a resource type) | http://www.openarchives.org/OAI/2.0/ | |
| oai_dc | (not a resource type) | http://www.openarchives.org/OAI/2.0/oai_dc/ | |
| dc | (not a resource type) | http://purl.org/dc/elements/1.1/ | |
| vg | Registry | http://www.ivoa.net/xml/VORegistry/v1.0 | |
| cs | ConeSearch | http://www.ivoa.net/xml/ConeSearch/1.0 | |
| sia | SimpleImageAccess | http://www.ivoa.net/xml/SIA/v1.1 | <a target="_blank" href="http://www.ivoa.net/xml/SIA/v1.0">http://www.ivoa.net/xml/SIA/v1.0</a> |
| ssap* | SimpleSpectralAccess | <a target="_blank" href="http://www.ivoa.net/xml/SSA/v1.1">http://www.ivoa.net/xml/SSA/v1.1</a> | <a target="_blank" href="http://www.ivoa.net/xml/SSA/v1.0">http://www.ivoa.net/xml/SSA/v1.0</a> or <a target="_blank" href="http://www.ivoa.net/xml/SSA/v0.4">http://www.ivoa.net/xml/SSA/v0.4</a>
|
| sn or osn | OpenSkyNode (deprecated) | (deprecated) | <a target="_blank" href="http://www.ivoa.net/xml/OpenSkyNode/v0.2">http://www.ivoa.net/xml/OpenSkyNode/v0.2</a>
|
tr
| TAP | http://www.ivoa.net/xml/TAPRegExt/v1.0 | |
| slap | SimpleLineAccess | http://www.ivoa.net/xml/SLAP/v1.0 | |
| vstd | VOStandard | http://www.ivoa.net/xml/StandardsRegExt/v1.0 | |
| xsi | (not a resource type) | http://www.w3.org/2001/XMLSchema-instance | |
| xsd | (not a resource type) | http://www.w3.org/2001/XMLSchema | |
| xlink | (not a resource type) | 'http://www.w3.org/1999/xlink | |