This document discusses arrays of objects in object-oriented programming. It outlines that a class can be used as a new data type, and arrays can be defined to hold multiple objects of that class. Methods can be used to manage arrays of objects, such as adding, deleting, and searching for objects. The document also explains that objects are passed by reference to methods rather than by value. An immutable class is defined as one that does not allow changes to its private data fields once an object is created. The document provides a full example of a contact book program that uses a Contact class and ManagArray class to store contact objects in an array and perform operations on them.