http://developer.apple.com/mac/library/documentation/Cocoa/Reference/Foundation/Protocols/NSMutableCopying_Protocol/Reference/Reference.html#//apple_ref/occ/intf/NSMutableCopying

For details on how copying works and what you should do, you can see this document (section 5.3 “Copy Operators”):
http://pierre.chachatelier.fr/programmation/fichiers/cpp-objc-en.pdf

I am glad that being beginner i know some of the things you mention above. I also strongly feel that being iPhone developer one should know these basics.

I think this mostly happens with people those come from big company. whereas for small companies one has to do lot’s of task and in that way he learn a lot. This is the only reason i started with small firm.

There is spelling mistake in line “you hear the terms “main run loop” or “event loop” for the firm time during the interview” it’s not firm it should be first.

can you tell what is “copy” or “mutableCopy” . i never heard this.
And Thanx for this informative article.