Difference between NSArray and NSMutableArray

Question

What is the difference b / w NSArray and NSMutableArray ?

Answer 1

NSMutableArray (and all other classes with Mutable in the name) can be changed. So, if you create a simple NSArray , you cannot change its contents later (without re-creating it). But if you create an NSMutableArray , you can change it - you will notice that it has methods like -addObject: and -insertObject:atIndex:

See the documentation for more details.

Answer 2

Volatile types are classes that can be changed after they are initialized, for example, NSMutableString vs NSString .

Answer 3

NSArray: in NSArray we cannot change the index .... The tool fixes the array.

NSMutableArray: in NSMutableArray we can change the index as well as add a value to the array at runtime.