ations where the cost of copper cable, such as category 5 cable, may be half or less than the cost of fiber. Now that we have an appreciation for the advan- tages and disadvantages associated with optical transmission systems, we will conclude this chapter by previewing the succeeding chapters in this book. As noted earlier in this chapter, you can use this information by itself or in conjunction with the index of this book to locate specific information if you wish to turn to a topic of immediate interest. Chapter Preview In this section we will preview the remaining chapters in this book. Although chapters were written to be as independent from one another as possible, readers new to this field should read chapters in the sequence presented. With that said, let's take our minitour of those chapters. Understanding Light In Chapter 2 we focus, no pun intended, on developing an appreciation for a phenomenon that we take for granted and of which we see only a portion. That phenomenon is light. In Chapter 2 we will examine the frequency spectrum, noting the different bands in the spectrum such as visible light, ultraviolet light, gamma rays, and other bands that stu- dents usually first became acquainted with during high school or col- lege physics. We will also review a variety of terms associated with light and will discuss power measurements that are important for determin- ing the performance level of an optical transmission system. Understanding Fiber For light to act as an optical transmission system, it must flow on a medi- um. That medium is fiber, which is the topic of Chapter 3. In that chapter Chapter One we will discuss the different types of fiber that can be used in an optical transmission system, how light flows down and through each type of fiber, and the advantages and disadvantages associated with the use of each type of fiber. Because it is important to understand the transmission char- acteristics of light as it flows into and through a fiber, we will also exam- ine many terms associated with lig