- u -
- U3D : HPS.Publish.Annotation
- Underlined : HPS.Publish.Border
- Universal3D : HPS.Exchange.File
- Unknown : HPS.Emergency , HPS.Exchange , HPS.Info , HPS.Publish.Image , HPS.StandAloneWindowEvent
- Unsupported : HPS.Exchange.File , HPS.Info
- UpdateOptions : HPS.SceneTree
- URL : HPS.Publish.Image
- User : HPS.Publish.Permission
- UserComponent : HPS.Component
- UserData : HPS.SceneTree , HPS.Search