When to use NSArray vs NSSet ?

Here is an explanation of when to use NSArray vs NSSet in Objective-C:

NSArray

• Use NSArray when you need an ordered collection of objects and the order of the objects matters.
• NSArray allows duplicate objects.
• You can access objects in an NSArray by index.
• NSArray has methods to add, insert, and remove objects at specific indexes.
• NSArray conforms to the NSCopying protocol, so you can create copies of arrays.

NSSet

• Use NSSet when you need an unordered collection of unique objects and the order does not matter.
• NSSet does not allow duplicate objects. If you add an object that is already in the set, nothing happens.
• You cannot access objects in an NSSet by index. You ...