An immutable, integer-indexed array of objects from the Apple Foundation framework.
An NSArray object manages an immutable array; once you have created the array, you cannot add, remove, or replace the objects in the array. You can, however, modify the individual elements themselves (if they support modification). The mutability of the collection does not affect the mutability of the objects inside the collection. You should use an immutable array if your data rarely changes, or changes all at once. Consider using a mutable array (nsmutablearray) if your data changes frequently.