OT: OGC Feature interface specifications

Hello All,
Which of the OGC specifications clearly documents the OGC Feature
interfaces?
I have being seeing many approaches to the OGC Feature implementations
and there seems to be no compatibility. Some implements FeatureClass, others
FeatureCollection. A document I read talked about FeatureCollection,
QueryableFeatureCollection, FeatureContainer, QueryableFeatureContainer etc.

Best regards,
Paul.