Most people believe that computers must be extremely complicated devices, because they perform such amazing tasks. To an extent, this is true. As you will learn later in this book, the closer you look at a computer’s operation, the more complex the system becomes. But like any machine, a computer is a collection of parts, which are categorized according to the kinds of work they do. Although there are many, many variations on the parts themselves, there are only a few major categories. 1/ you learn about those families of computer components and their basic functions, you will have mastered some of the most important concepts in computing. As you will see, the concepts are simple and easy to understand. This lesson gives you a glimpse inside a standard desktop computer and introduces you to its most important parts. You will learn how these components work together and allow you to interact with the system. You also will discover the importance of software, without which a computer could do nothing. Finally, you will see that the user is (in most cases, at least) an essential part of a complete computer system.