Difference between @interface declaration and @property declaration

Question

I\'m new to C, new to objective C. For an iPhone subclass, Im declaring variables I want to be visible to all methods in a class into the @interface class definition eg

Answer 1

Class A      

      @interface myclass : UIImageView {
    int aVar;
}

If you declare like this then you can only use this variable within your class A.


But suppose in Class B

    A *object=[A new];
object.aVar---->not available



For this you should **declare aVar as a property in Class A**

so class A should look like 

Class A      

  @interface myclass : UIImageView {
    int aVar;
}
@property int iVar;


and 


.m file 
@synthesize iVar;



So now you can use this iVar in another class Suppose B


 Class B
#import "Class A.h"

    enter code here

A *object=[A new];
object.aVar---->available
means
object.aVar=10;