Why you might use copy instead of strong in an Objective-c @property

This video covers the use of the objective-c @property attribute 'copy'. There is some confusion as to why you would use copy, and I try and illustrate how not using copy can still leave your class open to changes, even if you have a reference to an immutable NSString.
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Thanks.

[@pradeepsagar4312]

Marvellous :) it help a lot.Now my understanding on copy is clear. Thanks a lot.

[@ericrosko]

Glad it helped and thanks for checking out my old video! It's been a while since I've gotten a comment. I only wish I had time to do more of these.

[@aharonkreiter1833]

Great tutorial! Helped me understand it a little bit better!
I love the part where you say, "So, poor Bob. He didn't know anyone could change his data." XD

[@RiverOfTen]

Excellent explanation of copy vs strong semantics when dealing with objects that have mutable subclasses. Thank you!