This chapter introduced you to the concepts of arrays and objects. First, you learned about a few different types of arrays and how they are created and referenced. These array types were the numerically indexed array, associative array, and multidimensional array. Additionally, you saw examples of some of the numerous array-related functions already built into PHP. These functions can be used to manipulate and modify existing arrays, sometimes even creating entirely new ones.
In the second part of the chapter, you were given a foundation for working with object-oriented code. In no way does this content cover all the aspects of object-oriented programminguniversities teach entire series of classes (no pun intended) devoted to this topic, so you can imagine that these pages are a little light. However, you did learn to create classes and instantiate objects from them. You learned how to create and access the properties and methods of a class, how to build new classes, and how to inherit features from parent classes. That's not too shabby!