The book ends with two chapters which in a way reflect the style of Chapter 1, which provided the first overview of embedded systems and PIC microcontrollers. These last chapters return to overview mode, looking at some options for more advanced systems. The focus of the book overall has been on 8–bit PIC microcontrollers. That of course is only a tiny subset of the overall world of embedded systems, and the ambitious reader will want to know where he or she could move to next. Advanced systems often mean networked systems, so Chapter 20 surveys that field. Alternatively, advanced systems imply larger and more powerful microcontrollers, and Chapter 21 provides a first introduction to the 16- and 32-bit PIC microcontrollers.