Learning Objective-C 2.0: A Hands-on Guide to Objective-C for Mac and iOS Developers, Second Edition

B. Toll-Free Bridged Classes

Table B.1. Core Foundation Types That Are Toll-Free Bridged to Foundation Classes

Note

These are (currently) the only toll-free bridged classes. You should not use type or class names as a guide. If a class and type are not in the preceding table, they are not toll-free bridged, even if the class and type names are the same or similar.

See https://developer.apple.com/library/ios/#documentation/CoreFoundation/Conceptual/CFDesignConcepts/Articles/tollFreeBridgedTypes.html#//apple_ref/doc/uid/TP40010677-SW1.