Summary
This chapter provided an overview of the many different parts of Core Audio and gave you a taste of programming by using Audio File Services to get the metadata properties of audio files on the local drive. You saw how Core Audio uses properties as a crucial idiom for working with its various APIs. You also saw how Core Audio uses four character codes to specify property keys, and to signal errors.
Of course, you haven’t really dealt with audio itself yet. To do that, you first need to understand how sound is represented and handled in a digital form. Then you’ll be ready to dig into Core Audio’s APIs for working with audio data.