When subclassing NSObject, what difference does it make to import "Foundation.h" or "NSObject.h"?

Question

Here we see the same subclass of NSObject each using a different #import statement. What difference, if any, does this make for my subclass? What difference, if any, does this make for my final compiled program?

#import <Foundation/NSObject.h>
    @interface Card : NSObject

---

#import <Foundation/Foundation.h>
    @interface Card : NSObject

Answer 1

#import <Foundation/NSObject.h>
    @interface Card : NSObject

In this code ,you are only importing the NSObject class of Foundation framework,So you can't inherit the other classes of Foundation framework.

While

#import <Foundation/Foundation.h>
  @interface Card : NSObject

This code allow you to inherit any of the class provided by the Framework like NSProxy,NSRange etc.,as you are importing whole framework.

Hope it Helps....:)