Members of the class and object analysis

1, classes and objects can be stored members, members can categorize all, you can go all objects

2, used when the storage member is an object class associated with the class

3, when the object is stored in the storage member of the current object inside

4, when the object access a member, if the member does not object, try to access the same name as a member of the class, if the object   has this member, be sure to use members of the object