I'm just starting to use Objective-C and I need to clarify something When I @synthesize a @property, it is common convention to do the following: @interface Class : ParentClass @property propertyName @end @implementation @synthesize propertyName = _propertyName; @end I've seen plenty of questions and answers suggesting that "_propertyName" is widely accepted as the "correct" way to synthesize properties. However, does it serve ANY purpose? Or is it merely to increase readability and identify instance variables?