As PHP has evolved from a tool for building simple home pages to a language for serious Web development, so has its support for OOP. Once programs start to get larger and more complex, planning and design become more important. Think of a simple home page put together with some family photos, links, and blogs. Then think of a website like Amazon or eBay where there are thousands of forms, links, and transactions taking place all the time, all over the world the thought of putting something like that together is staggering. OOP is best suited to manage the complexity of such large websites. Even if you do not program using objects, if you are reading and using PHP programs written by other programmers, you are bound to run into this style of programming.
Like arrays, objects are composite types. They provide a way to organize a collection of data into a single unit. Object-oriented languages, such as C++ and Java, bundle up data into a variable and call it an object. So does PHP. Each object-oriented language you encounter is based on the same principles, but often the terminology is not exactly the same when describing the concepts. You could say that PHP is like Java and C++, but has its own way of dealing with objects.