What is the difference between "-copy" and "-copyWithZone:"?

Question

I know that a copy creates an immutable copy of an object, but I just want to know how copywithzone works and what is the main difference between copy and copywithzone

Answer 1

copy simply abbreviated for copyWithZone: using the default zone.

it is rarely what you call copyWithZone: directly, although a definition / implementation is required to accept @protocol NSCopying . therefore, you usually see copyWithZone: only in the implementation of copyWithZone: similarly, you usually avoid the copy implementation, and just let the default implementation of copy through copyWithZone:

Answer 2

NSZone is an outdated concept that has nothing to do with iOS. By default, NSObject on NSObject will call -copyWithZone: with the default zone.