Framework

From Cocoapedia

A Framework is a Bundle containing binary code, resources and supplemental files. The binary code can either be dynamically loadable or statically linked. Dynamic loadable frameworks - used on OSX - are installed in a shared location and loaded by apps at runtime. Statically linked libraries get merged into the app binary at compile time. The binary contained in a framework is a library.

Due to security concerns Apple decided to 'sandbox' iOS apps, binary code can only be loaded from the app's folder and only from the main binary. Therefore frameworks on iOS are usually statically linked libraries containing code for arm6, arm7 and i386 so that the same framework can be used for all iOS devices as well as iPhone simulator.