Chapter 3. Welcome to Objective-C

This chapter describes the core Objective-C language and how its syntax differs from Java. Functional differences and more esoteric language features are covered in later chapters.

Objective-C enhances C by adding an additional layer of syntax. It does not redefine C, or limit its capabilities, in any meaningful way. Objective-C syntax is easily recognized. If Objective-C had a logo, it would probably be the "at" sign (@); all Objective-C directives, including string constants, begin with @ (as in @interface, @selector(), @"string"). Other notable traits are the use of square brackets ([...]) to invoke methods and very descriptive method names.