Objective-C policies for properties:

From the stanford course:

Read-only vs. read-write:

@property int age; // read-write

@property (readonly) BOOL isHappy; // read-only

Memory management policies for object properties (not primitives)

@property (assign) NSString *name; // pointer assignment

@property (retain) NSString *name; // retain called

@property (copy) NSString *name; // copy called