Complex sentence: One example is the @ IBOutlet attribute, which marks a given value for use within Interface Builder (IB); an "outlet" is device that binds the value of the on-screen display to an object in code.
Split into simpler sentences: One example is the @ IBOutlet attribute, which marks a given value in the code as and "outlet", available for use within Interface Builder (IB). An "outlet" is device that binds the value of the on-screen display to an object in code.