my native languege is not English, please forgive me for my poor description to the question. i read the Entities document, there is a description about managed IComponentData: "Managed IComponentData must implement the IEquatable<T> interface and override for Object.GetHashCode()." Is it meaning that managed IComponentData may be a hash key? I dont read the source code, maybe is there hashmap to map managed IComponentData onto the entity? I just want to know why, if someone know it, please tell me. Thanks.