What is the difference between the attribute and instance variables are

The difference between instance variables and attributes are what
What is it all its own function
Just started looking confused objective-c.
Please give an example of a detailed description
Reply:
The main difference is in the scope.

Instance variables can only be accessed by members of the class itselfProperty provides open interfaces class, other classes can be accessed through the property.
Reply:

cited a floor reply:

major difference in the scope.

Instance variables can only be accessed by members of the class itselfProperty provides open interfaces class, other classes can be accessed through the property.

The scope is the same, the role of the data members are essentially like them, @ property and @ synthesize equivalent and you increase get, set method for your variables. Property is used. Operator access, you can use the pointer to access full member variable.