Mobile Manifest Entity
Okay, so Activities (DestinyActivityDefinition) take place in Destinations (DestinyDestinationDefinition). Destinations are part of larger locations known as Places (you're reading its documentation right now).

Places are more on the planetary scale, like "Earth" and "Your Mom."
Mapped to Mobile Manifest Table: Places
Type: object
Object Properties
The unique identifier for this entity. Guaranteed to be unique for the type of entity, but not globally.

When entities refer to each other in Destiny content, it is this hash that they are referring to.
Type: uint32
The index of the entity as it was found in the investment tables.
Type: int32
If this is true, then there is an entity with this identifier/type combination, but BNet is not yet allowed to show it. Sorry!
Type: boolean